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Agilent Technologies E1420B Скачать руководство пользователя страница 119

Absolute Measurement Fundamentals

5

Agilent E5505A User’s Guide

119

As long as these qualifications are met, and the software does not indicate any
difficulty in establishing its calibration criteria, an increase in PTR will not
degrade the system’s measurement accuracy.

The following methods may be considered for increasing or decreasing the
PTR.

Voltage controlled oscillators

1

Select a different VCO source that has the tuning capabilities needed for the
measurement.

2

Increase the tune range of the VCO source.

Signal generators

1

If you are using a signal generator with a calibrated 1 Vpk DC FM Input
(such as the Agilent 8640B, 8642A/B, 8656B, or 8662/3), the Voltage tuning
Range can be increased to 10 V as long as you select Computed from the
expected T. Constant in the Calibration Process display. These signal
generators continue to meet all of the previously mentioned tuning
qualifications across a 10 V tuning range.

2

Increase the signal generator’s frequency deviation setting and set the
software to measure the new tuning constant or enter the increased
deviation if it is known. (Note that increasing the deviation setting often
increases the source’s noise level as well.)

3

If you are using a synthesizer with Electronic-Frequency-Control (EFC)
capability such as the Agilent 8662A or Agilent 8663A, it is possible to
increase the tuning range of these sources using a VCO as an external time
base. When a compatible VCO source is connected to the EXT INPUT on the
8662/3, the tuning capability of the VCO source is transferred to the
synthesizer.

C A U TI ON

Be careful not to exceed the input voltage limitations of the Tune Port on the VCO
source

NO T E

Increasing the tune range of the VCO is only valid as long as the VCO source is able to
continuously meet the previously mentioned tuning qualifications.

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Содержание E1420B

Страница 1: ...Agilent Technologies Agilent E5505A Phase Noise Measurement System User s Guide First edition June 2004 ...

Страница 2: ...the performance of a U S Government prime contract or sub contract Software is delivered and licensed as Commercial computer soft ware as defined in DFAR 252 227 7014 June 1995 or as a commercial item as defined in FAR 2 101 a or as Restricted computer software as defined in FAR 52 227 19 June 1987 or any equivalent agency regulation or contract clause Use duplication or disclosure of Software is ...

Страница 3: ... 35 How to begin 35 Powering the System On 36 To power on a racked system 36 To power on a benchtop system 36 Starting the Measurement Software 37 Figure 4 Navigation to the E5500 user interface 37 Figure 5 Phase noise measurement subsystem main screen 38 Performing a Confidence Test 39 Figure 6 Opening the file containing pre stored parameters 39 Figure 7 Navigating to the Define Measurement wind...

Страница 4: ...ion of validity of L f 52 4 Expanding Your Measurement Experience Starting the Measurement Software 54 Figure 19 Navigate to E5500 user interface 54 Using the Asset Manager 55 Configuring an asset 55 Figure 20 Navigate to Asset Manager 55 Figure 21 Navigate to Add in Asset Manager 56 Figure 22 Select source as asset type 56 Figure 23 Choose source 57 Figure 24 Select I O library 57 Figure 25 Enter...

Страница 5: ...w measurement 71 Figure 44 Connection diagram 72 Table 6 Test set signal input limits and characteristics 73 Sweep segments 75 Figure 45 Oscilloscope display of beatnote from test set monitor port 76 Making the measurement 76 Figure 46 Selecting suppression 77 Figure 47 Typical phase noise curve for an 8663A 10 MHz measurement 78 Table 7 Parameter data for the 8663A 10 MHz measurement 79 Testing t...

Страница 6: ...isplaying the Parameter Summary 99 Figure 65 Navigate to parameter summary 99 Figure 66 Parameter summary 100 Exporting Measurement Results 101 Figure 67 Export results choices 101 Exporting Trace Data 102 Figure 68 Trace data results 102 Exporting spur data 103 Figure 69 Spur data results 103 Exporting X Y data 104 Figure 70 X Y data results 104 5 Absolute Measurement Fundamentals The Phase Lock ...

Страница 7: ...g Injection Locking 120 Adding Isolation 120 Increasing the PLL Bandwidth 120 Figure 79 Peak tuning range PTR Required by injection locking 121 Inserting a Device 122 An attenuator 122 Figure 80 Measurement noise floor relative to R Port signal level 122 An amplifier 123 Figure 81 Measurement noise floor as a result of an added attenuator 123 Evaluating Noise Above the Small Angle Line 124 Determi...

Страница 8: ...asurement 143 Free Running RF Oscillator 145 Required equipment 145 Defining the measurement 145 Figure 97 Select the parameters definition file 146 Figure 98 Enter source information 147 Table 17 Tuning characteristics for various sources 147 Selecting a reference source 148 Figure 99 Selecting a reference source 148 Selecting Loop Suppression Verification 148 Figure 100 Selecting loop suppressio...

Страница 9: ...166 Table 21 Test set signal input limits and characteristics 167 Checking the beatnote 167 Figure 118 Oscilloscope display of beatnote from the test set Monitor port 168 Making the measurement 169 Figure 119 Selecting suppressions 169 Figure 120 Typical phase noise curve for an RF synthesizer using DCFM 170 Table 22 Parameter Data for the RF Synthesizer DCFM Measurement 171 RF Synthesizer Using E...

Страница 10: ...op suppression verification 191 Setup considerations for the microwave source measurement 191 Figure 137 Noise characteristics for the microwave measurement 191 Beginning the measurement 192 Figure 138 Selecting a new measurement 192 Figure 139 Confirm measurement dialog box 192 Figure 140 Connect diagram for the microwave source measurement 193 Table 27 Test set signal input limits and characteri...

Страница 11: ... ranges 215 Procedure 216 Figure 154 Measuring power from splitter 216 Table 32 Acceptable amplitude ranges for the phase detectors 216 Figure 155 Calibration source beatnote injection 217 Synthesized residual measurement using beatnote cal 217 Table 33 Frequency Ranges 217 Procedure 218 Figure 156 Synthesized residual measurement using beatnote cal 218 Double Sided spur 218 Figure 157 Calibration...

Страница 12: ...oscope for determining voltage peaks 238 Figure 175 Adjust phase difference at phase detector 239 Figure 176 Adjust phase shifter until meter indicates 0 volts 240 When the measurement is complete 240 Figure 177 Typical phase noise curve for a residual measurement 241 Table 38 Parameter data for the amplifier measurement example 241 9 FM Discriminator Fundamentals The Frequency Discriminator Metho...

Страница 13: ...ent is complete 264 Figure 198 Typical phase noise curve using double sided spur calibration 264 Table 42 Parameter data for the double sided spur calibration example 265 Discriminator Measurement using FM Rate and Deviation Calibration 267 Required equipment 267 Table 43 Required equipment for the FM discriminator measurement example 267 Determining the discriminator delay line length 268 Figure ...

Страница 14: ...se system with external detector 285 Figure 219 AM Noise system with 70429A Opt K21 AM detector 286 Figure 220 AM noise system with N5507A downconverter 286 AM detector 286 Figure 221 AM detector schematic 286 Table 46 Maximum carrier offset frequency 287 Calibration and Measurement General Guidelines 289 Method 1 User Entry of Phase Detector Constant 290 Method 1 example 1 290 Figure 222 Phase de...

Страница 15: ...diagram tab 305 Figure 243 Select graph description on graph tab 306 Beginning the measurement 307 Figure 244 Selecting a new measurement 307 Figure 245 Confirm measurement dialog box 307 Figure 246 Connect diagram for the AM noise measurement 308 Table 47 Test set signal input limits and characteristics 309 Figure 247 Connect diagram example 309 Making the measurement 310 When the measurement is ...

Страница 16: ...ur Measurement Results Evaluating the Results 324 Looking for obvious problems 324 Figure 260 Noise plot showing obvious problems 325 Comparing against expected data 325 Figure 261 Compensation for added reference source noise 326 Figure 262 Measurement results and reference source noise 327 Gathering More Data 328 Repeating the measurement 328 Figure 263 Repeating a measurement 328 Doing more res...

Страница 17: ... suppression curve 348 Figure 275 Smoothed loop suppression curve 349 Figure 276 Theoretical loop suppression curve 349 Figure 277 Smoothed vs theoretical loop suppression curve 350 Figure 278 Smoothed vs Adjusted theoretical loop suppression curve 350 Figure 279 Adjusted theoretical vs theoretical loop suppression curve 351 PLL gain change 352 Maximum error 352 Accuracy degradation 352 Blanking F...

Страница 18: ...66 Tune Range of VCO for Center Voltage 367 Figure 295 Tune range of VCO for center voltage 367 Peak Tuning Range Required by Noise Level 368 Figure 296 Typical source noise level vs minimum tuning range 368 Phase Lock Loop Bandwidth vs Peak Tuning Range 369 Figure 297 PLL BW vs peak tuning range 369 Noise Floor Limits Due to Peak Tuning Range 370 Figure 298 Noise at source s peak tuning range 370...

Страница 19: ...to access special functions 381 Figure 302 8665A special functions keys 381 Description of Special Functions 120 and 124 381 8665B Frequency Limits 383 Table 64 8665B frequency limits 383 8665B mode keys 383 Table 65 Operating characteristics for 8665B modes 2 and 3 384 How to access special functions 384 Figure 303 8665B Special functions keys 384 Description of special functions 120 and 124 385 ...

Страница 20: ...lation Overview 406 PC Digitizer Software Phase 1 407 To install the PC digitizer software 407 Hardware Installation 408 Preparing for installation 408 Figure 310 Remove screws from side of CPU 408 Figure 311 Slide cover off 409 Figure 312 Remove hold down bar 409 Accessing PC expansion slots 410 Figure 313 Vertically Mounted expansion slots 410 Taking ESD precautions 410 Installing the PC digitiz...

Страница 21: ...es 435 Figure 328 Choose model and serial number 436 Figure 329 Select internal in baseband source 436 Figure 330 Enter a comment about the configured asset 437 Figure 331 Asset manager screen showing configured PC Digitizer 437 Configuring the Agilent E4411A B ESA L1500A Swept Analyzer 438 License Key for the Phase Noise Test Set 439 Figure 332 Navigate to E5500 asset manager 439 Figure 333 Navig...

Страница 22: ...Instrument 462 To remove a half width instrument from a system rack 462 Figure 339 Instrument lock links front and rear 463 Benchtop Instrument 463 To remove an instrument from a benchtop system 463 Instrument Installation 464 Standard rack instrument 464 To install an instrument 464 Half Rack Width instrument 465 To install the instrument in a rack 465 Benchtop instrument 465 To install an instru...

Страница 23: ...e 78 German noise requirements summary 473 Compliance with Canadian EMC requirements 473 Service and Support 474 Agilent on the Web 474 Return Procedure 475 Determining your instrument s serial number 475 Figure 340 Serial number location 475 Shipping the instrument 476 To package the instrument for shipping 476 ...

Страница 24: ...24 Agilent E5505A User s Guide ...

Страница 25: ...25 E5505A Phase Noise Measurement System User s Guide Agilent Technologies 1 Getting Started Introduction 26 Documentation Map 27 Additional Documentation 28 System Overview 29 ...

Страница 26: ...surement fundamentals to get you started Use Table 1 on page 27 as a guide to Learning about the E5505A phase noise measurement system Learning about phase noise basics and measurement fundamentals Using the E5505A system to make specific phase noise measurements In this guide you ll also find information on system connections and specifications and procedures for re installing phase noise specifi...

Страница 27: ...Chapter 7 Residual Measurement Fundamentals Chapter 8 Residual Measurement Examples Chapter 9 FM Discriminator Fundamentals Chapter 10 FM Discriminator Measurement Examples Chapter 11 AM Noise Measurement Fundamentals Chapter 12 AM Noise Measurement Examples Chapter 13 Baseband Noise Measurement Examples Chapter 14 Evaluating Your Measurement Results Chapter 15 Advanced Software Features Chapter 1...

Страница 28: ...nu for additional information The E5505A system documentation includes Agilent E5505A Phase Noise Measurement System Installation Guide Agilent E5505A Phase Noise Measurement System User s Guide Agilent N5501A N5502A Phase Noise Downconverter User s Guide Agilent N5507A Phase Noise Downconverter User s Guide Agilent N5500A Phase Noise Test Set User s Guide Agilent E5500 Series Phase Noise Measurem...

Страница 29: ...ne instruments to work in the system This standalone instrument architecture easily configures for various measurement techniques including the phase lock loop PLL reference source technique and delay line and FM discriminator methods The E5505A system is available as a one bay wide System II rack and as a benchtop model Due to the system s flexibility the hardware in the system varies greatly wit...

Страница 30: ...ith earlier systems and instruments including the MMS mainframe You may easily integrate existing assets into your E5505A system Table 2 shows the E5505A instruments and earlier model equivalents Figure 2 E5505A benchtop system typical configuration Table 2 Equivalent system instrument model numbers System or Instrument New Number Old Number Phase noise measurement system E5505A E5501A E5501B E550...

Страница 31: ...m User s Guide Agilent Technologies 2 Introduction and Measurement Introducing the GUI 32 Designing to Meet Your Needs 34 E5505A Operation A Guided Tour 35 Powering the System On 36 Performing a Confidence Test 39 Powering the System Off 45 ...

Страница 32: ...n the defining process The system provides three default segment tables To obtain a quick look at your data select the fast quality level If it is important to have more frequency resolution to separate spurious signals use the normal and high resolution quality levels If you need to customize the offset range beyond the defaults provided tailor the measurement segment tables to meet your needs an...

Страница 33: ...Introduction and Measurement 2 Agilent E5505A User s Guide 33 S ystemRequ irements Figure 3 E5500 graphical user interface GUI E5500_main_screen 24 Jun 04 rev 2 ...

Страница 34: ... the system s basic measurement capabilities Beginning The section E5505A Operation A Guided Tour on page 35 contains a step by step procedure for completing a phase noise measurement This measurement demonstration introduces system operating fundamentals for whatever type of device you plan to measure Once you are familiar with the information in this chapter you should be prepared to start Chapt...

Страница 35: ...se noise measurement system offers enormous flexibility for measuring the noise characteristics of your signal sources and two port devices Required equipment The equipment shipped with this system is all that is required to complete this demonstration Refer to the E5505A Phase Noise Measurement System Installation Guide if you need information about setting up the hardware or installing the softw...

Страница 36: ...connected to a safety power strip turn the strip s power switch to the on position 3 Allow the system to warm up for 30 minutes WARNING Before applying power make sure the AC power input and the location of the system meet the requirements given in Table 4 on page 14 Failure to do so may result in damage to the system or personal injury NOTE Warm up Time The downconverter and RF source instruments...

Страница 37: ...he E5500 phase noise measurement software disk in the CD ROM drive 2 Using Windows Start menu as in Figure 4 navigate to the E5500 User Interface 3 The phase noise measurement subsystem main screen appears Figure 5 on page 38 Figure 4 Navigation to the E5500 user interface E5500_start_menu 04 Apr 04 rev 1 ...

Страница 38: ...nt Figure 5 Phase noise measurement subsystem main screen E5500_main_screen 24 Jun 04 rev 2 NOTE The default background for the screen is gray You can change the background color by selecting View Display Preferences and clicking on the Background Color button ...

Страница 39: ... 2 If necessary choose the drive or directory where the file you want is stored 3 In the File Name box select Confidence pnm Figure 6 4 Click the Open button The appropriate measurement definition parameters for this example have been pre stored in this file Table 3 on page 44 lists the parameter data that has been entered for the N5500A confidence test example 5 To view the parameter data in the ...

Страница 40: ...se button Beginning a measurement 1 From the Measure menu choose New Measurement See Figure 8 Figure 7 Navigating to the Define Measurement window e5505a_users_nav_define_wind 24 Jun 04 rev 3 Figure 8 Navigating to the New Measurement window E5500_new_measurement 04 Apr 04 rev 1 ...

Страница 41: ...m dialog box appears connect the 50 Ω termination provided with your system to the test set s noise input connector Refer to Figure 10 on page 41 for more information about the correct placement of the 50 Ω termination Figure 9 Confirm new measurement Figure 10 Setup diagram displayed during the confidence test E5500_new_cali_meas 04 Apr 04 rev 1 E5500_verify_con 23 Mar 04 rev 1 50 Ω termination ...

Страница 42: ... REF INPUT PHASE DET OUTPUT N5500A Standard Test Set N5500A OPT 001 TEST SET GPIB STATUS INPUT SIGNAL 50 kHz 26 5 GHz 100 kHz 100 MHz 50 W 20mA MAX 50 W 1V Pk 100 W 1 25 LPS 0 01 Hz 100 MHz 15 dBm MIN 7 dBm MIN RF ANALYZER ANALYZER ANALYZER NOISE MONITOR 50 kHz 1600MHz 1 2 26 5 GHz OUT OF LOCK TUNE VOLTAGE TO DOWNCONVERTER FROM DOWNCONVERTER REF INPUT PHASE DET OUTPUT N5500A Opt 001 Test Set N5500...

Страница 43: ...bles the system to optimize measurement speed while providing you with the measurement resolution needed for most test applications Congratulations You have completed a phase noise measurement This measurement of the test set s low noise amplifier provides a convenient way to verify that the system hardware and software are properly configured for making noise measurements If your graph looks like...

Страница 44: ...e analyzers configured in your phase noise system 2 Cal Tab Gain preceding noise input 0 dB 3 Block Diagram Tab Noise Source Test Set Noise Input 4 Test Set Tab Input Attenuation LNA Low Pass Filter LNA Gain DC Block PLL Integrator Attenuation 0 dB 20 MHz Auto checked Auto Gain Minimum Auto Gain 14 dB Not checked 0 dBm 5 Graph Tab Title Graph Type X Scale Minimum X Scale Maximum Y Scale Minimum Y ...

Страница 45: ...rrors and restores functionality to the system If you still receive errors after running the E5500 Shutdown utility call your local Agilent Technologies Service Center To run the E5500 Shutdown utility 1 Double Click on the E5500 Shutdown utility shortcut on the PC desktop and follow the onscreen instructions You can also navigate to it using the menu path Start Agilent Subsystems E5500 Phase Nois...

Страница 46: ...46 Agilent E5505A User s Guide 2 Introduction and Measurement ...

Страница 47: ...47 E5505A Phase Noise Measurement System User s Guide Agilent Technologies 3 Phase Noise Basics What is Phase Noise 48 Phase terms 49 ...

Страница 48: ...parts per million per hour day month or year Short term stability contains all elements causing frequency changes about the nominal frequency of less than a few seconds duration The chapter deals with short term stability Mathematically an ideal sinewave can be described by Where nominal amplitude linearly growing phase component and nominal frequency But an actual signal is better modeled by Wher...

Страница 49: ... in an oscillator include thermal noise shot noise and flicker noise Many terms exist to quantify the characteristic randomness of phase noise Essentially all methods measure the frequency or phase deviation of the source under test in the frequency or time domain Since frequency and phase are related to each other all of these terms are also related Spectral density One fundamental description of...

Страница 50: ...RF analyzer Figure 16 shows that the National Institute of Standards and Technology NIST defines L f as the ratio of the power at an offset f Hertz away from the carrier The phase modulation sideband is based on a per Hertz of bandwidth spectral density and or offset frequency in one phase modulation sideband on a per Hertz of bandwidth spectral density and f equals the Fourier frequency or offset...

Страница 51: ...n dB relative to the carrier per Hz dBc Hz as shown in Figure 17 This chapter except where noted otherwise uses the logarithmic form of as follows Figure 16 Deriving L f from a RF analyzer display Figure 17 L f Described Logarithmically as a Function of Offset Frequency e5505a_user_derivingL_RF_display ai rev2 10 20 03 L f L f S f f 2f2 L f e5505a_user_log_offset_freq ai rev2 10 20 03 ...

Страница 52: ...5 dB more noise power at a 1 Hz offset in a 1 Hz bandwidth than in the total power of the signal which is of course invalid Figure 18 shows a 10 dB decade line drawn over the plot indicating a peak phase deviation of 0 2 radians integrated over any one decade of offset frequency At approximately 0 2 radians the power in the higher order sidebands of the phase modulation is still insignificant comp...

Страница 53: ...ting the Measurement Software 54 Using the Asset Manager 55 Using the Server Hardware Connections to Specify the Source 60 Testing the 8663A Internal External 10 MHz 66 Testing the 8644B Internal External 10 MHz 81 Viewing Markers 96 Omitting Spurs 97 Displaying the Parameter Summary 99 Exporting Measurement Results 101 ...

Страница 54: ...1 Make sure your computer and monitor are turned on 2 Place the E5500 Phase Noise Measurement System software disk in the disc holder and insert in the CD ROM drive 3 Using Figure 19 as a guide navigate to the E5500 User Interface Figure 19 Navigate to E5500 user interface E5500_start_menu 04 Apr 04 rev 1 ...

Страница 55: ...guring the asset Verifying the server hardware connections Configuring an asset This procedure demonstrates how to add an asset to the E5505A system 1 Using Figure 20 as a guide navigate to Asset Manager For this example we invoke the Asset Manager Wizard from the E5500 main screen This is the most common way to add assets WARNING Be sure to power off the system before making all hardware connecti...

Страница 56: ...set Manager window See Figure 21 3 From the Asset Type pull down list in Choose Asset Role dialog box select Source then click Next See Figure 22 Figure 21 Navigate to Add in Asset Manager Figure 22 Select source as asset type E5500_add_source2 16 Apr 04 rev 1 E5500_add_source3 16 Apr 04 rev 1 ...

Страница 57: ...lect GPIB0 See Figure 24 6 In the Address box type 19 7 In the Library pull down list select the Agilent Technologies VISA Click the Next button Figure 23 Choose source E5500_add_source4 16 Apr 04 rev 1 NOTE 19 is the default address for a source Table 4 on page 63 shows the default GPIB address for all system instruments Figure 24 Select I O library E5500_add_source5 16 Apr 04 rev 1 ...

Страница 58: ...ts corresponding serial number Click the Next button See Figure 25 9 In the Enter A Comment dialog box you may type a comment that associates itself with the asset you have just configured Click Finish See Figure 26 Figure 25 Enter asset and serial number Figure 26 Enter comment E5500_add_source6 16 Apr 04 rev 1 E5500_add_source7 16 Apr 04 rev 1 ...

Страница 59: ...et Manager displays a message verifying the connection to your asset This indicates that you have successfully configured a source See Figure 28 11 To exit the Asset Manager on the menu select Server Exit 12 Perform the procedure Using the Server Hardware Connections to Specify the Source on page 60 Figure 27 Click check mark button Figure 28 Confirmation message E5500_add_source8 16 Apr 04 rev 1 ...

Страница 60: ...Connections to Specify the Source 1 From the System menu choose Server Hardware Connections See Figure 29 2 Select the Sources tab shown in Figure 30 Figure 29 Navigate to server hardware connections Figure 30 Select Sources tab E5500_add_source10 16 Apr 04 rev 1 E5500_add_source11 16 Apr 04 rev 1 ...

Страница 61: ...ssfully performed by the software If nothing happens click the Check I O button to manually initiate the check b A red circle with a slash appears if the I O check is unsuccessful c If the I O check fails click the Asset Manager button to return to the Asset Manager see Figure 32 Figure 31 Successful I O check Figure 32 Failed I O check E5500_add_source12 16 Apr 04 rev 1 E5500_add_source13 16 Apr ...

Страница 62: ...configured correctly Do the following Check your system hardware connections Click the green check mark button on the Asset Manager s toolbar to verify connectivity Return to Server Hardware Connections and click the Check I O button to re check it NOTE Use the same process to add additional assets to your E5505A system ...

Страница 63: ...in the easy procedure starting on page 64 Table 4 Default GPIB addresses Instrument Address Test set 20 Downconverter 28 Microwave downconverter 28 RF analyzer 17 FFT analyzer PC digitizer card 1 FFT analyzer 89410A 18 Source 1 19 Source 2 23 Counter 3 Agilent E1430 VXI digitizer1 1 The E5500 software supports this instrument although it is not part of the standard E5505A system 129 Agilent E1437 ...

Страница 64: ... On the E5500 main menu select System Asset Manager See Figure 33 2 Double Click on the desired instrument in the Asset Manager list left pane See Figure 34 Figure 33 Asset Manager on System menu Figure 34 Asset Manager window E5500_asset_manager 23 Mar 04 rev 1 E5500_asset_mgr_screen 23 Mar 04 rev 1 ...

Страница 65: ...xit the Asset Manager on the menu select Server Exit Next proceed to one of the following absolute measurements using either an Agilent 8257x or an Agilent 8644B source Testing the 8663A Internal External 10 MHz on page 66 Testing the 8644B Internal External 10 MHz on page 81 Figure 35 GPIB address dialog box E5500_edit_asset_info 04 Apr 04 rev 1 ...

Страница 66: ...the E5500 User Interface choose Open If necessary choose the drive or directory where the file you want is stored 2 In the File Name box choose Conf_SigGen_10MHz pnm See Figure 36 CAUTION To prevent damage to the test set s hardware components do not apply the input signal to the signal input connector until the input attenuator has been correctly set for the desired configuration as shown in Tabl...

Страница 67: ... Enter the same frequency for the detector input frequency b Enter the VCO Nominal Tuning Constant see Table 5 on page 68 c Enter the Tune Range of VCO see Table 5 d Enter the Center Voltage of VCO see Table 5 e Enter the Input Resistance of VCO see Table 5 NOTE Note that the source parameters entered for step 2 in Table 7 on page 79 may not be appropriate for the reference source you are using To...

Страница 68: ...r Freq Tuning Constant Hz V Center Voltage V Voltage Tuning Range V Input Resistance Ω Tuning Calibration Method Agilent 8662 3A EFC DCFM υ0 5 E 9 x υ0 FM Deviation 0 0 10 10 1E 6 1 K 8662 600 8663 Measure Compute Compute Agilent 8642A B FM Deviation 0 10 600 Compute Agilent 8644B FM Deviation 0 10 600 Compute Other Signal Generator DCFM Calibrated for 1V FM Deviation 0 10 Rin Compute Other User V...

Страница 69: ...these operations click the Close button Setting up for the 8663A 10 MHz measurement The signal amplitude at the test set s R input Signal Input port sets the measurement noise floor level Use Figure 40 on page 70 and Figure 41 on page 70 to help determine the amplitude required to provide a noise floor level that is below the expected noise floor of your DUT For more information about this graph r...

Страница 70: ... Noise floor for the 8663 10 MHz measurement Figure 41 Noise floor example 140 160 170 180 150 Expected phase noise floor of system dBc Hz f 10kHz R Port signal level dBm 15 15 5 5 n5505a_exp_phase_noise 25 Feb 04 rev 1 L Port level 15dBm e5505a_user_noise_floor_ex 24 Jun 04 rev 3 ...

Страница 71: ...the amplifiers noise will have on the measured noise floor Beginning the measurement 1 From the Measurement menu choose New Measurement See Figure 42 2 When the Do you want to perform a New Calibration and Measurement prompt appears click Yes 3 When the Connect Diagram dialog box appears click on the hardware pull down arrow and select your hardware configuration from the list See Figure 44 on pag...

Страница 72: ...outine or stop it 6 Press Continue using Adjusted Loop Suppression to continue making the noise measurement or press Abort to stop the measurement For descriptions of the messages see Status messages on page 74 You have time to read through the descriptions while the system completes the routines Figure 44 Connection diagram E5500_verify_con 23 Mar 04 rev 1 CAUTION The test set s signal input is s...

Страница 73: ...Bm 0 to 20 dBm Downconverters N5502A 70422A N5507A 70427A 0 to 30 dBm 5 to 15 dBm Characteristics Input Impedance 50 Ω nominal AM Noise DC coupled to 50 Ω load NOTE Refer to the following system connect diagram examples in Chapter 18 System Interconnections for more information about system interconnections Figure 307 E5505A system connections with standard test set on page 401 Figure 308 E5505A s...

Страница 74: ...e tuning range of the VCO source you are using when you set up your own Phase Lock Loop measurements Zero beating sources The center frequencies of the sources are now adjusted if necessary to position the beatnote within the 5 range The adjustment is made with the tune voltage applied to the VCO source set at its nominal or center position Measuring the VCO Tuning Constant The tuning sensitivity ...

Страница 75: ...sure that the center frequencies of the two sources are close enough in frequency to create a beatnote that is within the Capture Range of the system The phase lock loop PLL Capture Range is 5 of the peak tuning range of the VCO source you are using The peak tuning range for your VCO can be estimated by multiplying the VCO tuning constant by the tune range of VCO Refer to Chapter 14 Evaluating You...

Страница 76: ...e ready to make the measurement 2 When the PLL Suppression Curve dialog box appears check View Measured Loop Suppression View Smoothed Loop Suppression and View Adjusted Loop Suppression in the lower right of the dialog box See Figure 46 on page 77 Figure 45 Oscilloscope display of beatnote from test set monitor port 0V 1V div E5505a_oscillo_disp_beatnote 25 Feb 04 rev 1 ...

Страница 77: ...on curve this is the predicted loop suppression based on the initial loop parameters defined selected for this particular measurement kphi kvco loop bandwidth filters gain and others Adjusted theoretical suppression curve this is the new adjusted theoretical value of suppression for this measurement It is based on changing loop parameters in the theoretical response to match the smoothed measured ...

Страница 78: ... Expanding Your Measurement Experience Table 7 on page 79 contains the data stored in the parameter definitions file Figure 47 Typical phase noise curve for an 8663A 10 MHz measurement e5505a_user_typ_noise_curve_8663a 24 Jun 04 rev 3 ...

Страница 79: ...Hz same as Carrier Source Frequency 16 dBm 1 E 3 Hz V 10 Volts 0 Volts 600 ohms 3 Cal Tab Phase Detector Constant VCO Tune Constant Phase Lock Loop Suppression If Limit is exceeded Measure Phase Detector Constant Calculate from expected VCO Tune Constant Verify calculated phase locked loop suppression Show Suppression Graph 4 Block Diagram Tab Carrier Source Downconverter Reference Source Timebase...

Страница 80: ... of Shift trace data DOWN by Trace Smoothing Amount Power present at input of DUT Confidence Test using Agilent 8663A Int vs Ext 10 MHz Single sideband Noise dBc Hz 10 Hz 4 E 6 Hz 0 dBc Hz 170 dBc Hz 1 Hz bandwidth 1 times the current carrier frequency 0 dB 0 0 dB 1 The Stop Frequency depends on the analyzers configured in your phase noise system Table 7 Parameter data for the 8663A 10 MHz measure...

Страница 81: ...A User Interface choose Open If necessary choose the drive or directory where the file you want is stored 2 In the File Name box choose Conf_8644B_10MHz pnm See Figure 42 CAUTION To prevent damage to the test set s hardware components do not apply the input signal to the signal input connector until the input attenuator has been correctly set for the desired configuration as shown in Table 8 on pa...

Страница 82: ... frequency for the detector input frequency b Enter the VCO Nominal Tuning Constant see Table 8 on page 83 c Enter the Tune Range of VCO see Table 8 on page 83 d Enter the Center Voltage of VCO see Table 8 on page 83 e Enter the Input Resistance of VCO see Table 8 on page 83 NOTE The source parameters shown in Table 10 on page 94 may not be appropriate for the reference source you are using To cha...

Страница 83: ...stics for various sources VCO Source Carrier Freq Tuning Constant Hz V Center Voltage V Voltage Tuning Range V Input Resistance Ω Tuning Calibration Method Agilent 8662 3A EFC DCFM υ0 5 E 9 x υ0 FM Deviation 0 0 10 10 1E 6 1 K 8662 600 8663 Measure Compute Compute Agilent 8642A B FM Deviation 0 10 600 Compute Agilent 8644B FM Deviation 0 10 600 Compute Other Signal Generator DCFM Calibrated for 1V...

Страница 84: ... then choose the Cal tab from the Define Measurement window 2 In the Cal dialog box check Verify calculated phase locked loop suppression and Always Show Suppression Graph Select If limit is exceeded Show Loop Suppression Graph See Figure 51 on page 85 3 When you have completed these operations click the Close button Figure 50 Selecting a reference source e5505_user_select_ref_source8644 24 Jun 04...

Страница 85: ...2 and the example in Figure 53 on page 86 to determine the amplitude For more information refer to Chapter 16 Reference Graphs and Tables Figure 51 Selecting loop suppression verification e5505a_user_select_loop 24 Jun 04 rev 3 Figure 52 Noise floor for the 8644B 10 MHz measurement 140 160 170 180 150 Expected phase noise floor of system dBc Hz f 10kHz R Port signal level dBm 15 15 5 5 n5505a_exp_...

Страница 86: ...n adequate measurement noise floor it is necessary to insert a low noise amplifier between the DUT and the test set Refer to the section Inserting a Device on page 122 for details on determining the effect the amplifier s noise will have on the measured noise floor Figure 53 Noise floor example e5505a_user_noise_floor_ex 24 Jun 04 rev 3 ...

Страница 87: ...d select your hardware configuration from the list See Figure 56 on page 88 CAUTION To prevent damage to the test set s hardware components do not apply the input signal to the signal input connector until the input attenuator has been correctly set for the desired configuration as shown in Table 9 on page 89 Apply the input signals when the connection diagram appears as in step 3 below Figure 54 ...

Страница 88: ...r stop it 6 Press Continue using Adjusted Loop Suppression to continue making the noise measurement or press Abort to stop the measurement For descriptions of the messages see Status messages on page 74 You have time to read through the descriptions while the system completes the routines Figure 56 Connect diagram dialog box e5505a_conn_diag_dialog rev 1 23 jun 04 CAUTION The test set s signal inp...

Страница 89: ...ed in the setup is a VCO As you see later in this demonstration you are required to estimate the tuning range of the VCO source you are using when you set up your own Phase Lock Loop measurements Table 9 Test set signal input limits and characteristics Limits Frequency 50 kHz to 26 5 GHz Maximum Signal Input Power 30 dBm At Attenuator Output Operating Level Range RF Phase Detectors Microwave Phase...

Страница 90: ...t places the noise graph on its display As you watch the graph you see the system plot its measurement results in frequency segments The system measures the noise level across its frequency offset range by averaging the noise within smaller frequency segments This technique enables the system to optimize measurement speed while providing you with the measurement resolution needed for most test app...

Страница 91: ...he beatnote requires that you adjust the center frequency of one of the sources above and below the frequency of the other source until the beatnote appears on the oscilloscope s display See Figure 57 If incrementing the frequency of one of the sources does not produce a beatnote you need to verify the presence of an output signal from each source before proceeding NOTE If the center frequencies o...

Страница 92: ... Software Features a Measured loop suppression curve this is the result of the loop suppression measurement performed by the E5505A system b Smoothed measured suppression curve this is a curve fit representation of the measured results it is used to compare with the theoretical loop suppression c Theoretical suppression curve this is the predicted loop suppression based on the initial loop paramet...

Страница 93: ...surement is complete refer to Chapter 14 Evaluating Your Measurement Results for help in evaluating your measurement results Figure 59 on page 93 shows a typical phase noise curve for an RF Synthesizer Table 10 on page 94 contains the data stored in the parameter definitions file Figure 59 Typical phase noise curve for an 8644B 10 MHz measurement E5505A_user_typ_noise_curve_8644B 24 Jun 04 rev 3 ...

Страница 94: ...tance 10 E 6 Hz 7 dBm Test Set 10 E 6 Hz 10 E 6 Hz same as Carrier Source Frequency 16 dBm 1 E 3 Hz V 10 Volts 0 Volts 600 ohms 3 Cal Tab Phase Detector Constant VCO Tune Constant Phase Lock Loop Suppression If Limit is exceeded Measure Phase Detector Constant Calculate from expected VCO Tune Constant Verify calculated phase locked loop suppression Show Suppression Graph 4 Block Diagram Tab Carrie...

Страница 95: ... Scale trace data to a new carrier frequency of Shift trace data DOWN by Trace Smoothing Amount Power present at input of DUT Confidence Test using Agilent 8644B Int vs Ext 10 MHz Single sideband Noise dBc Hz 10 Hz 4 E 6 Hz 0 dBc Hz 170 dBc Hz 1 Hz bandwidth 1 times the current carrier frequency 0 dB 0 0 dB 1 The stop frequency depends on the analyzers configured in your phase noise system Table 1...

Страница 96: ...sults graph To access the marker function on the View menu click Markers See Figure 60 In the dialog box containing Marker buttons up to nine markers may be added To remove a highlighted marker click the Delete button See Figure 61 Figure 60 Navigate to markers Figure 61 Adding and deleting markers e5505a_user_nav_markers 24 Jun 04 rev 3 e5505a_user_add_delete_markers 24 Jun 04 rev 3 ...

Страница 97: ... click Display Preferences See Figure 62 2 In the Display Preferences dialog box uncheck Spurs and click OK See Figure 63 The graph is displayed without spurs See Figure 64 on page 98 3 To re display the spurs check Spurs in the Display Preferences dialog box Figure 62 Navigate to display preferences Figure 63 Uncheck spurs e5505a_user_nav_display_pref 24 Jun 04 rev 3 e5505a_user_uncheck_spurs ai ...

Страница 98: ...98 Agilent E5505A User s Guide 4 Expanding Your Measurement Experience Figure 64 Graph displayed without spurs e5505a_user_graph_without_spurs 24 Jun 04 rev 3 ...

Страница 99: ...tries that were used for this measurement The parameter summary data is included when you print the graph 1 On the View menu click Parameter Summary See Figure 65 2 The Parameter Summary Notepad dialog box appears The data can be printed or changed using standard Notepad functionality See Figure 66 on page 100 Figure 65 Navigate to parameter summary e5505a_user_nav_param_sum 24 Jun 04 rev 3 ...

Страница 100: ... E5505A User s Guide 4 Expanding Your Measurement Experience Figure 66 Parameter summary e5505a_user_text_param_sum 24 Jun 04 rev 3 Agilent N5502A Agilent 8644B VCO tuned using DCFM Agilent 8644B Int vs Ext 10 MHz ...

Страница 101: ...lts function exports data in one of three types Exporting Trace Data Exporting Spur Data Exporting X Y Data 1 To export measurement results on the File menu point to Export Results then click on either Trace Data Spur Data or X Y Data See Figure 67 Figure 67 Export results choices e5505a_user_export_result_choices 24 Jun 04 rev 3 ...

Страница 102: ...e 4 Expanding Your Measurement Experience Exporting Trace Data 1 On the File menu point to Export Results then click on Trace Data See Figure 68 on page 102 Figure 68 Trace data results e5505a_user_trace_data_results 24 Jun 04 rev 3 ...

Страница 103: ...ment Experience 4 Agilent E5505A User s Guide 103 Exporting spur data 1 On the File menu point to Export Results then click on Spur Data See Figure 69 Figure 69 Spur data results e5505a_user_spur_data_results 24 Jun 04 rev 3 ...

Страница 104: ...User s Guide 4 Expanding Your Measurement Experience Exporting X Y data 1 On the File menu point to Export Results then click on X Y Data See Figure 70 Figure 70 X Y data results e5505a_user_xy_data_result 24 Jun 04 rev 3 ...

Страница 105: ...undamentals The Phase Lock Loop Technique 106 What Sets the Measurement Noise Floor 110 Selecting a Reference 112 Estimating the Tuning Constant 115 Tracking Frequency Drift 116 Changing the PTR 118 Minimizing Injection Locking 120 Inserting a Device 122 Evaluating Noise Above the Small Angle Line 124 ...

Страница 106: ...of the sources is the DUT The second source serves as the reference against which the DUT is measured One of the two sources must be a VCO source capable of being frequency tuned by the System Figure 71 shows a simplified diagram of the PLL configuration used for the measurement The Phase Lock Loop Circuit The Capture and Drift tracking ranges Like other PLL circuits the phase lock loop created fo...

Страница 107: ... voltage tuning range Volts PTR VCO Tuning Sensitivity X Total Voltage Tuning Range PTR 100 Hz V X 10 V 1000 Hz As an Example A Peak Tuning Range of 1000 Hz provides the following ranges Capture Range 0 05 X 1000 Hz 50 Hz Drift Tracking Range 0 24 X 1000 Hz 240 Hz Tuning requirements The peak tuning range required for your measurement depends on the frequency stability of the two sources you are u...

Страница 108: ...he VCO source Although you must select a VCO source that provides a sufficient tuning range to permit the system to track the beatnote keep in mind that a wide tuning range typically means a higher noise level on the VCO source signal When the VCO source for your measurement is also the reference source this trade off can make reference source selection the most critical aspect of your measurement...

Страница 109: ...05A User s Guide 109 Input Resistance of Tuning Port ohms if the tuning constant is not to be measured The measurement examples in the next chapter that recommend a specific VCO source provides you with the tuning parameters for the specified source ...

Страница 110: ... range shown in Table 11 the signal level at the R Signal Input port sets the noise floor for the system Figure 74 shows the relationship between the R signal input level and the system noise floor Table 11 Amplitude ranges for L and R ports Phase Detector 50 kHz to 1 6 GHz 1 2 to 26 5 GHz1 1 Phase noise test set Options 001 and 201 with no attenuation 50 kHz to 26 5 GHz2 2 Phase noise test set Op...

Страница 111: ...is at or below the level of the source you are going to measure Figure 75 demonstrates that as the noise level of the reference source approaches the noise level of the DUT the level measured by the System which is the sum of all noise sources affecting the system is increased above the actual noise level of the DUT Figure 75 Reference source noise approaches DUT noise 15 10 5 4 3 2 1 0 5 1 0 1 5 ...

Страница 112: ...are able to use a device similar to the DUT as the reference source for your PLL measurement Of course one of the devices must be capable of being voltage tuned by the system to do this To select a similar device for use as the reference source you must establish that the noise level of the reference source device is adequate to measure your DUT The Three Source Comparison technique enables you to...

Страница 113: ...rovides the test system with sufficient capture and drift tracking ranges to maintain lock throughout the measurement To make this determination you must estimate what the drift range of the sources you are using will be over the measurement period thirty minutes maximum Details on the relationship between the capture and drift tracking ranges and the tuning range of the VCO source are provided in...

Страница 114: ... a factor of 2 10 to 10 See Figure 77 1 E 6 Measure Table 12 Tuning Characteristics of Various VCO Source Options continued VCO Source Carrier Freq Tuning Constant Hz V Center Voltage V Voltage Tuning Range V Input Resistance Ω Tuning Calibration Method Figure 77 Voltage tuning range limits relative to center voltage of the VCO tuning curve e5505a_user_tune_range_VCO ai rev2 10 24 03 ...

Страница 115: ...bration Process menu Table 13 lists the calibration method choices and the tuning constant accuracy required for each Table 13 VCO tuning constant calibration method VCO Tuning Constant Calibration Method selected in calibration screen Required Tuning Constant Accuracy entered in parameter screen Use the current tuning constant must be accurate from a previous measurement of the same source Within...

Страница 116: ...r the measurement If beatnote drift prevents the beatnote from remaining within the Capture Range long enough for the system to attain phase lock the computer informs you by displaying a message If the beatnote drifts beyond the drift tracking range during the measurement the computer stops the measurement and inform you that the system has lost lock Evaluating beatnote drift The Checking the Beat...

Страница 117: ...rnatives 1 Minimize beatnote drift By Allowing sources to warm up sufficiently By Selecting a different reference source with less drift 2 Increase the capture and drift tracking Ranges By Selecting a measurement example in this chapter that specifies a drift rate compatible with the beatnote drift rate you have observed By Increasing the peak tuning range for the measurement Further information a...

Страница 118: ...ment An important attribute of the PLL bandwidth is that it suppresses the close in noise which would otherwise prevent the system from locking the loop The Tuning Qualifications Changing the PTR is accomplished by changing the tune range of VCO value or the VCO tuning constant value or both There are several ways this can be done However when considering these or any other options for changing th...

Страница 119: ...ese signal generators continue to meet all of the previously mentioned tuning qualifications across a 10 V tuning range 2 Increase the signal generator s frequency deviation setting and set the software to measure the new tuning constant or enter the increased deviation if it is known Note that increasing the deviation setting often increases the source s noise level as well 3 If you are using a s...

Страница 120: ...ion locking bandwidth is less or equal to the PLL bandwidth it may be possible to increase the PLL bandwidth sufficiently to complete the measurement The PLL bandwidth is increased by increasing the peak tuning range PTR for the measurement To estimate the PTR needed to prevent injection locking from causing the system to lose lock 1 Determine the injection locking bandwidth Tune the beatnote towa...

Страница 121: ...e required PLL bandwidth in Figure 79 to determine the PTR required for the measurement For details on increasing the PTR refer to Changing the PTR in this section Figure 79 Peak tuning range PTR Required by injection locking Required PPL bandwidth Hz 1 10 100 1k 10k 100k 1M 10M 100M 1G 1 100 1 10 100k 1k 1M 10k E5505a_PTR_reqd_inj_lock 25 Mar 04 rev 1 Peak tuning range Hz ...

Страница 122: ...deration when inserting an attenuator is that the signal source has sufficient output amplitude to maintain the required signal level at the test set s phase detector input port The signal level required for the measurement depends on the noise floor level needed to measure the DUT Figure 80 shows the relationship between the signal level at the R port and the measurement noise floor Figure 80 Mea...

Страница 123: ...f the source The Agilent N5507A Option K22 dual RF amplifier was designed specifically for this purpose This instrument is the preferred solution for tests requiring an external amplifier Use the following equation to estimate what the measurement noise floor is as a result of the added noise of an inserted amplifier Figure 81 shows an example L f out 174 dB Amplifier Noise Figure Power into Ampli...

Страница 124: ...n the display Determining the Phase Lock Loop bandwidth 1 Determine the Peak Tuning Range PTR of your VCO by multiplying the VCO Tuning Constant by the Tune Range of VCO value entered If the phase noise software has measured the VCO Tuning Constant use the measured value For Example 2 Estimate the Phase Lock Loop PLL bandwidth for the measurement using the PTR of your VCO and the graph in Figure 8...

Страница 125: ...vided by the peak tuning range Required PPL bandwidth Hz 1 10 100 1k 10k 100k 1M 10M 100M 1G 1 100 1 10 100k 1k 1M 10k E5505a_PTR_reqd_inj_lock 25 Mar 04 rev 1 Peak tuning range Hz NOTE If you are not able to tune the beatnote to 2 X PLL bandwidth center of display due to frequency drift refer to Tracking Frequency Drift in this section for information about measuring drifting signals If you are a...

Страница 126: ...gle line at all offset frequencies beyond the PLL bandwidth The small angle line applies only to the level of the average noise Spur levels that exceed the small angle line do not degrade measurement accuracy provided they do not exceed 40 dBc 7 Continue moving the marker to the right to verify that the average noise level remains below the small angle line 8 Increase the span by a factor of ten b...

Страница 127: ... measurement options 1 Evaluate your source using the noise data provided by the RF analyzer in the procedure you just performed 2 Increase the PTR if possible to provide a sufficient PLL bandwidth to suppress the noise For information on increasing the PTR refer to Changing the PTR in this section 3 Reduce the noise level of the signal sources 4 Use the Discriminator technique to measure the phas...

Страница 128: ...128 Agilent E5505A User s Guide 5 Absolute Measurement Fundamentals ...

Страница 129: ...e Measurement System User s Guide Agilent Technologies 6 Absolute Measurement Examples Stable RF Oscillator 130 Free Running RF Oscillator 145 RF Synthesizer Using DCFM 160 RF Synthesizer Using EFC 173 Microwave Source 187 ...

Страница 130: ...ng the measurement 1 From the File menu of the E5500 User Interface choose Open 2 If necessary choose the drive or directory where the file you want is stored 3 In the file name box choose StableRF pnm See Figure 85 CAUTION To prevent damage to the test set s components do not apply the input signal to the signal input connector until the input attenuator has been correctly set for the desired con...

Страница 131: ...GHz Enter the same frequency for the detector input frequency b Enter the VCO nominal Tuning Constant For values see Table 14 on page 132 c Enter the Tune Range of VCO see Table 14 d Enter the Center Voltage of VCO see Table 14 e Enter the Input Resistance of VCO see Table 14 NOTE Note that the source parameters entered for step 2 in Table 16 on page 143 may not be appropriate for the reference so...

Страница 132: ...s VCO Source Carrier Freq Tuning Constant Hz V Center Voltage V Voltage Tuning Range V Input Resistance Ω Tuning Calibration Method Agilent 8662 3A EFC DCFM υ0 5 E 9 x υ0 FM Deviation 0 0 10 10 1E 6 1 K 8662 600 8663 Measure Compute Compute Agilent 8642A B FM Deviation 0 10 600 Compute Agilent 8644B FM Deviation 0 10 600 Compute Other Signal Generator DCFM Calibrated for 1V FM Deviation 0 10 Rin C...

Страница 133: ...ression Verification 1 Using Figure 88 on page 134 as a guide navigate to the Cal tab 2 In the Cal dialog box check Verify calculated phase locked loop suppression and Always Show Suppression Graph Select If limit is exceeded Show Loop Suppression Graph Figure 87 Selecting a reference source e5505a_user_select_ref_source 24 Jun 04 rev 3 Agilent 8257 ...

Страница 134: ... Input port sets the measurement noise floor level Use Figure 89 on page 135 and Figure 90 on page 135 to determine the amplitude required to provide a noise floor level that is below the expected noise floor of your DUT The Checking the Beatnote procedure in this section will provide you with an opportunity to estimate the measurement noise floor that your DUT will provide Figure 88 Selecting loo...

Страница 135: ...or the stable RF oscillator measurement Figure 90 Noise floor calculation example 140 160 170 180 150 Expected phase noise floor of system dBc Hz f 10kHz R Port signal level dBm 15 15 5 5 n5505a_exp_phase_noise 25 Feb 04 rev 1 L Port level 15dBm e5505a_user_noise_floor_ex 24 Jun 04 rev 3 ...

Страница 136: ...source is used as the reference source In order for the noise measurement results to accurately represent the noise of the DUT the noise level of the reference source should be below the expected noise level of the DUT For additional help in selecting an appropriate reference source refer to Chapter 6 Absolute Measurement Examples Beginning the measurement 1 From the Measurement menu choose New Me...

Страница 137: ...DUT and reference sources to the test set at this time Confirm your connections as shown in the connect diagram The input attenuator Option 001 only is now correctly configured based on your measurement definition Figure 93 Connect diagram for the stable RF oscillator measurement E5500_verify_con 23 Mar 04 rev 1 CAUTION The test set s signal input is subject to the limits and characteristics in Ta...

Страница 138: ...ent N5502A 70422A 0 to 30 dBm Agilent N5507A 70427A 5 to 15 dBm Characteristics Input Impedance 50 Ω nominal AM Noise DC coupled to 50 Ω load CAUTION To prevent damage to the test set s hardware components do not apply the input signal to the test set s signal input connector until the input attenuator Option 001 has been set by the phase noise software which occurs at the connection diagram NOTE ...

Страница 139: ...Chapter 14 Evaluating Your Measurement Results if you are not familiar with the relationship between the PLL capture range and the peak tuning range of the VCO The beatnote frequency is set by the relative frequency difference between the two sources If you have two very accurate sources set at the same frequency the resulting beatnote will be very close to 0 Hz Searching for the beatnote will req...

Страница 140: ...e check and are ready to make the measurement 2 When the PLL Suppression Curve dialog box appears select View Measured Loop Suppression View Smoothed Loop Suppression and View Adjusted Loop Suppression See Figure 95 on page 141 Figure 94 Oscilloscope display of beatnote from test set Monitor port 0V 1V div E5505a_oscillo_disp_beatnote 25 Feb 04 rev 1 ...

Страница 141: ... curve this is the predicted loop suppression based on the initial loop parameters defined selected for this particular measurement kphi kvco loop bandwidth filters gain etc d Adjusted theoretical suppression curve this is the new adjusted theoretical value of suppression for this measurement It is based on changing loop parameters in the theoretical response to match the smoothed measured curve a...

Страница 142: ...142 Agilent E5505A User s Guide 6 Absolute Measurement Examples Figure 96 Typical phase noise curve for a stable RF oscillator e5505a_user_typ_noise_curve_RFosc 24 Jun 04 rev 3 ...

Страница 143: ...Reference Source Power Nominal Tune Constant Tune Range Center Voltage Input Resistance Maximum Allowed Deviation from Center Voltage 100 E 6 Hz 8 dBm Test Set 100 E 6 Hz 100 E 6 Hz same as Carrier Source Frequency 16 dBm 40 E 3 Hz V 10 Volts 0 Volts 1 E 6 Ω 1 Volts 3 Cal Tab Phase Detector Constant VCO Tune Constant Phase Lock Loop Suppression Measure Phase Detector Constant Calculate VCO Tune Co...

Страница 144: ...0 dBm 6 Downconverter Tab The downconverter parameters do not apply to this measurement example 7 Graph Tab Title Graph Type X Scale Minimum X Scale Maximum Y Scale Minimum Y Scale Maximum Normalize trace data to a Scale trace data to a new carrier frequency of Shift trace data DOWN by Trace Smoothing Amount Power present at input of DUT Stable RF Oscillator vs Similar Reference Source Single side...

Страница 145: ...onnect the DUT and reference source to the test set Defining the measurement 1 From the File menu of the E5500 User Interface choose Open 2 If necessary choose the drive or directory where the file you want is stored 3 In the File Name box choose FreeRF pnm See Figure 97 CAUTION To prevent damage to the test set s components do not apply the input signal to the signal input connector until the inp...

Страница 146: ...DUT 5 MHz to 1 6 GHz Enter the same frequency for the detector input frequency f Enter the VCO Nominal Tuning Constant see Table 17 on page 147 g Enter the Tune Range of VCO see Table 17 h Enter the Center Voltage of VCO see Table 17 i Enter the Input Resistance of VCO see Table 17 Figure 97 Select the parameters definition file NOTE Note that the source parameters entered for step 2 in Table 16 o...

Страница 147: ...put Resistance Ω Tuning Calibration Method Agilent 8662 3A EFC DCFM υ0 5 E 9 x υ0 FM Deviation 0 0 10 10 1E 6 1 K 8662 600 8663 Measure Compute Compute Agilent 8642A B FM Deviation 0 10 600 Compute Agilent 8644B FM Deviation 0 10 600 Compute Other Signal Generator DCFM Calibrated for 1V FM Deviation 0 10 Rin Compute Other User VCO Source Estimated within a factor of 2 10 to 10 1 E 6 Measure e5505a...

Страница 148: ...u have completed these operations click the Close button Selecting Loop Suppression Verification 1 Using Figure 100 on page 149 as a guide navigate to the Cal tab 2 In the Cal dialog box check Verify calculated phase locked loop suppression and Always Show Suppression Graph Select If limit is exceeded Show Loop Suppression Graph Figure 99 Selecting a reference source e5505a_user_select_ref_source ...

Страница 149: ...gnal Input port sets the measurement noise floor level Use Figure 101 on page 150 and Figure 102 on page 150 to determine the amplitude required to provide a noise floor level that is below the expected noise floor of your DUT The Checking the Beatnote procedure in this section will provide you with an opportunity to estimate the measurement noise floor that your DUT will provide Figure 100 Select...

Страница 150: ...the free running RF oscillator measurement Figure 102 Noise floor calculation example 140 160 170 180 150 Expected phase noise floor of system dBc Hz f 10kHz R Port signal level dBm 15 15 5 5 n5505a_exp_phase_noise 25 Feb 04 rev 1 L Port level 15dBm e5505a_user_noise_floor_ex 24 Jun 04 rev 3 ...

Страница 151: ...s noise will have on the measured noise floor VCO reference In order for the noise measurement results to accurately represent the noise of the DUT the noise level of the reference source should be below the expected noise level of the DUT Beginning the measurement 1 From the Measurement menu choose New Measurement See Figure 103 2 When the Do you want to perform a New Calibration and Measurement ...

Страница 152: ...ly is now correctly configured based on your measurement definition Figure 105 Connect diagram for the free running RF oscillator measurement e5505a_user_connect_free_osc 24 Jun 04 rev 3 TEST SET DOWNCONVERTER N5500A N5502A CAUTION The test set s signal input is subject to the limits and characteristics in Table 18 on page 153 To prevent damage to the test set s components do not apply the input s...

Страница 153: ...limits and characteristics Limits Frequency 50 kHz to 1 6 GHz Std 50 kHz to 26 5 GHz Option 001 50 kHz to 26 5 GHz Option 201 Maximum Signal Input Power Sum of the reference and signal input power shall not exceed 23 dBm At Attenuator Output Operating Level Range RF Phase Detectors 0 to 23 dBm Signal Input 15 to 23 dBm Reference Input Microwave Phase Detectors 0 to 5 dBm Signal Input 7 to 10 dBm R...

Страница 154: ... the beatnote requires you to adjust the center frequency of one of the sources above and below the frequency of the other source until the beatnote appears on the oscilloscope s display If incrementing the frequency of one of the sources does not produce a beatnote you need to verify the presence of an output signal from each source before proceeding NOTE If the center frequencies of the sources ...

Страница 155: ... Measured Loop Suppression View Smoothed Loop Suppression and View Adjusted Loop Suppression See Figure 107 on page 156 NOTE If you are able to locate the beatnote but it distorts and then disappears as you adjust it towards 0 Hz your sources are injection locking to each other Set the beatnote to the lowest frequency possible before injection locking occurs and then refer to Minimizing Injection ...

Страница 156: ...on curve this is the predicted loop suppression based on the initial loop parameters defined selected for this particular measurement kphi kvco loop bandwidth filters gain etc d Adjusted theoretical suppression curve this is the new adjusted theoretical value of suppression for this measurement It is based on changing loop parameters in the theoretical response to match the smoothed measured curve...

Страница 157: ...Absolute Measurement Examples 6 Agilent E5505A User s Guide 157 Figure 108 Typical phase noise curve for a free running RF oscillator e5505a_user_typ_noise_free_osc ai rev2 10 21 03 ...

Страница 158: ...Hz 4 dBm Test Set 444 E 6 Hz 444 E 6 Hz same as Carrier Source Frequency 16 dBm 40 E 3 Hz V 10 Volts 0 Volts 600 ohms 3 Cal Tab Phase Detector Constant VCO Tune Constant Phase Lock Loop Suppression If Limit is exceeded Measure Phase Detector Constant Calculate from expected VCO Tune Constant Verify calculated phase locked loop suppression Show Suppression Graph 4 Block Diagram Tab Carrier Source D...

Страница 159: ...uto Microwave Millimeter Band Millimeter Band Mixer Bias Enable Current Reference Chain Reference External Tune Enable Tuning Sensitivity Nominal 100 MHz PLL Bandwidth 600 MHz PLL Bandwidth 10 044 E 9 Auto 444 E 6 0 20 dBM 0 dBm 0 dB 0 dB Checked Microwave 0 to 26 5 GHz Unchecked 0 mA 10 MHz Unchecked 0 ppm v 0 ppm V 126 Hz 10000 Hz Table 19 Parameter data for the free running RF oscillator measur...

Страница 160: ...e measurement 1 From the File menu choose Open 2 If necessary choose the drive or directory where the file you want is stored 3 In the File Name box choose RFSynth_DCFM pnm See Figure 109 CAUTION To prevent damage to the test set s components do not apply the input signal to the signal input connector until the input attenuator has been correctly set for the desired configuration as shown in Table...

Страница 161: ...6 GHz Enter the same frequency for the detector input frequency b Enter the VCO Nominal Tuning Constant see Table 20 on page 162 c Enter the Tune Range of VCO see Table 20 d Enter the Center Voltage of VCO see Table 20 e Enter the Input Resistance of VCO see Table 20 NOTE Note that the source parameters entered for step 2 in Table 22 on page 171 may not be appropriate for the reference source you ...

Страница 162: ...er Freq Tuning Constant Hz V Center Voltage V VoltageTuning Range V Input Resistance Ω Calibration Method Agilent 8662 3A EFC DCFM υ0 5 E 9 x υ0 FM Deviation 0 0 10 10 1E 6 1 K 8662 600 8663 Measure Compute Compute Agilent 8642A B FM Deviation 0 10 600 Compute Agilent 8644B FM Deviation 0 10 600 Compute Other Signal Generator DCFM Calibrated for 1V FM Deviation 0 10 Rin Compute Other User VCO Sour...

Страница 163: ...n Graph 3 When you have completed these operations click the Close button Setup considerations for the RF synthesizer using DCFM measurement Measurement noise floor The signal amplitude at the test set s R input Signal Input port sets the measurement noise floor level Use Figure 113 and Figure 114 on page 164 to determine the amplitude required to provide a noise floor level that is below the expe...

Страница 164: ...for the RF synthesizer DCFM measurement Figure 114 Noise floor calculation example 140 160 170 180 150 Expected phase noise floor of system dBc Hz f 10kHz R Port signal level dBm 15 15 5 5 n5505a_exp_phase_noise 25 Feb 04 rev 1 L Port level 15dBm e5505a_user_noise_floor_ex 24 Jun 04 rev 3 ...

Страница 165: ...floor Agilent 8663A VCO reference This setup uses the 8663A as the VCO reference source In order for the noise measurement results to accurately represent the noise of the DUT the noise level of the reference source should be below the expected noise level of the DUT Beginning the measurement 1 From the Measurement menu choose New Measurement See Figure 103 2 When the Do you want to perform a New ...

Страница 166: ...Option 001 only is now correctly configured based on your measurement definition A Figure 117 Connect diagram for the RF synthesizer DCFM measurement e5505_user_connect_diag_8663a 24 Jun 04 rev 3 N5500A CAUTION The test set s signal input is subject to the limits and characteristics in Table 21 on page 167 To prevent damage to the test set s hardware components do not apply the input signal to the...

Страница 167: ...acteristics Limits Frequency 50 kHz to 1 6 GHz Std 50 kHz to 26 5 GHz Option 001 50 kHz to 26 5 GHz Option 201 Maximum Signal Input Power Sum of the reference and signal input power shall not exceed 23 dBm At Attenuator Output Operating Level Range RF Phase Detectors 0 to 23 dBm Signal Input 15 to 23 dBm Reference Input Microwave Phase Detectors 0 to 5 dBm Signal Input 7 to 10 dBm Reference Input ...

Страница 168: ...beatnote will require that you adjust the center frequency of one of the sources above and below the frequency of the other source until the beatnote appears on the oscilloscope s display If incrementing the frequency of one of the sources does not produce a beatnote you will need to verify the presence of an output signal from each source before proceeding NOTE If the center frequencies of the so...

Страница 169: ...ware Features a Measured loop suppression curve this is the result of the loop suppression measurement performed by the E5505A system b Smoothed measured suppression curve this is a curve fit representation of the measured results it is used to compare with the theoretical loop suppression c Theoretical suppression curve this is the predicted loop suppression based on the initial loop parameters d...

Страница 170: ... curve as closely as possible When the measurement is complete refer to Chapter 14 Evaluating Your Measurement Results for help with using the results Figure 120 shows a typical phase noise curve for an RF synthesizer using DCFM Figure 120 Typical phase noise curve for an RF synthesizer using DCFM e5505a_user_typ_noise_curve_8663a 24 Jun 04 rev 3 ...

Страница 171: ...nce 600 E 6 Hz 20 dBm Test Set 600 E 6 Hz 600 E 6 Hz same as Carrier Source Frequency 16 dBm 40 E 3 Hz V 10 Volts 0 Volts 600 Ω 3 Cal Tab Phase Detector Constant VCO Tune Constant Phase Lock Loop Suppression If Limit is exceeded Measure Phase Detector Constant Calculate from expected VCO Tune Constant Verify calculated phase locked loop suppression Show Suppression Graph 4 Block Diagram Tab Carrie...

Страница 172: ...Y Scale Maximum Normalize trace data to a Scale trace data to a new carrier frequency of Shift trace data DOWN by Trace Smoothing Amount Power present at input of DUT RF Synthesizer vs Agilent 8663A using DCFM Single sideband Noise dBc Hz 10 Hz 4 E 6 Hz 0 dBc Hz 170 dBc Hz 1 Hz bandwidth 1 times the current carrier frequency 0 dB 0 0 dB Table 22 Parameter Data for the RF Synthesizer DCFM Measureme...

Страница 173: ...est set Defining the measurement 1 From the File menu choose Open 2 If necessary choose the drive or directory where the file you want is stored 3 In the File Name box choose RFSynth_EFC pnm See Figure 121 CAUTION To prevent damage to the test set s components the input signal do not apply the signal input connector until the input attenuator has been correctly set for the desired configuration as...

Страница 174: ...on page 189 c If you are going to use EFC tuning to tune the 8663A use the following equation to calculate the appropriate VCO Tuning Constant to enter for the measurement VCO Tuning Constant T x Carrier Frequency Where T 5E 9 for EFC For example to calculate the Tuning Constant value to enter for EFC tuning when the center frequency is 300 MHz 5 E 9 X 300 E 6 1500 E 3 1 5 d Enter the Tune Range o...

Страница 175: ...nput Resistance Ω Tuning Calibration Method Agilent 8662 3A EFC DCFM υ0 5 E 9 x υ0 FM Deviation 0 0 10 10 1E 6 1 K 8662 600 8663 Measure Compute Compute Agilent 8642A B FM Deviation 0 10 600 Compute Agilent 8644B FM Deviation 0 10 600 Compute Other Signal Generator DCFM Calibrated for 1V FM Deviation 0 10 Rin Compute Other User VCO Source Estimated within a factor of 2 10 to 10 1 E 6 Measure e5505...

Страница 176: ...u have completed these operations click the Close button Selecting Loop Suppression Verification 1 Using Figure 124 on page 177 as a guide navigate to the Cal tab 2 In the Cal dialog box check Verify calculated phase locked loop suppression and Always Show Suppression Graph Select If limit is exceeded Show Loop Suppression Graph Figure 123 Selecting a reference source e5505a_user_select_ref_source...

Страница 177: ... The signal amplitude at the test set s R input Signal Input port sets the measurement noise floor level Use Figure 125 and Figure 126 on page 178 to determine the amplitude required to provide a noise floor level that is below the expected noise floor of your DUT Figure 124 Selecting Loop suppression verification e5505a_user_select_loop 24 Jun 04 rev 3 ...

Страница 178: ...for the RF synthesizer EFC measurement Figure 126 Noise floor calculation example 140 160 170 180 150 Expected phase noise floor of system dBc Hz f 10kHz R Port signal level dBm 15 15 5 5 n5505a_exp_phase_noise 25 Feb 04 rev 1 L Port level 15dBm e5505a_user_noise_floor_ex 24 Jun 04 rev 3 ...

Страница 179: ...floor Agilent 8663A VCO reference This setup uses the 8663A as the VCO reference source In order for the noise measurement results to accurately represent the noise of the DUT the noise level of the reference source should be below the expected noise level of the DUT Beginning the measurement 1 From the Measurement menu choose New Measurement See Figure 127 2 When the Do you want to perform a New ...

Страница 180: ...Option 001 only is now correctly configured based on your measurement definition A Figure 129 Connect diagram for the RF synthesizer EFC measurement e5505_user_connect_diag_8663a 24 Jun 04 rev 3 N5500A CAUTION The test set s signal input is subject to the limits and characteristics in Table 24 on page 181 To prevent damage to the test set s hardware components do not apply the input signal to the ...

Страница 181: ...Limits and Characteristics Limits Frequency 50 kHz to 1 6 GHz Std 50 kHz to 26 5 GHz Option 001 50 kHz to 26 5 GHz Option 201 Maximum Signal Input Power Sum of the reference and signal input power shall not exceed 23 dBm At Attenuator Output Operating Level Range RF Phase Detectors 0 to 23 dBm Signal Input 15 to 23 dBm Reference Input Microwave Phase Detectors 0 to 5 dBm Signal Input 7 to 10 dBm R...

Страница 182: ...n the oscilloscope s display If incrementing the frequency of one of the sources does not produce a beatnote you will need to verify the presence of an output signal from each source before proceeding Making the measurement 1 Click the Continue button when you have completed the beatnote check and are ready to make the measurement 2 When the PLL Suppression Curve dialog box appears select View Mea...

Страница 183: ...ical loop suppression c Theoretical suppression curve this is the predicted loop suppression based on the initial loop parameters defined selected for this particular measurement kphi kvco loop bandwidth filters gain etc d Adjusted theoretical suppression curve this is the new adjusted theoretical value of suppression for this measurement It is based on changing loop parameters in the theoretical ...

Страница 184: ...uide 6 Absolute Measurement Examples Figure 132 shows a typical phase noise curve for a RF synthesizer using EFC Figure 132 Typical phase noise curve for an RF synthesizer using EFC e5505a_user_typ_noise_curve_EFC 24 Jun 04 rev 3 ...

Страница 185: ...nce 500 E 6 Hz 10 dBm Test Set 500 E 6 Hz 500 E 6 Hz same as Carrier Source Frequency 16 dBm 2 5 Hz V 10 Volts 0 Volts 1 E 6 ohms 3 Cal Tab Phase Detector Constant VCO Tune Constant Phase Lock Loop Suppression If Limit is exceeded Measure Phase Detector Constant Measure from expected VCO Tune Constant Verify calculated phase locked loop suppression Show Suppression Graph 4 Block Diagram Tab Carrie...

Страница 186: ... Y Scale Maximum Normalize trace data to a Scale trace data to a new carrier frequency of Shift trace data DOWN by Trace Smoothing Amount Power present at input of DUT RF Synthesizer vs Agilent 8663A using EFC Single sideband Noise dBc Hz 10 Hz 4 E 6 Hz 0 dBc Hz 170 dBc Hz 1 Hz bandwidth 1 times the current carrier frequency 0 dB 0 0 dB Table 25 Parameter data for the RF synthesizer EFC measuremen...

Страница 187: ...eference source to the test set Defining the measurement 1 From the File menu choose Open 2 If necessary choose the drive or directory where the file you want is stored 3 In the File Name box choose MicroSRC pnm See Figure 133 CAUTION To prevent damage to the test set s components do not apply the input signal to the signal input connector until the input attenuator has been correctly set for the ...

Страница 188: ...Table 26 on page 189 Use the following equation to calculate the appropriate VCO Tuning Constant to enter for the measurement VCO Tuning Constant T x Carrier Frequency where T 5E 9 For example to calculate the Tuning Constant value to enter for EFC tuning when the center frequency is 18 GHz 5 E 9 X 18 E 9 90 c Enter the Tune Range of VCO see Table 26 on page 189 d Enter the Center Voltage of VCO s...

Страница 189: ...nput Resistance Ω Tuning Calibration Method Agilent 8662 3A EFC DCFM υ0 5 E 9 x υ0 FM Deviation 0 0 10 10 1E 6 1 K 8662 600 8663 Measure Compute Compute Agilent 8642A B FM Deviation 0 10 600 Compute Agilent 8644B FM Deviation 0 10 600 Compute Other Signal Generator DCFM Calibrated for 1V FM Deviation 0 10 Rin Compute Other User VCO Source Estimated within a factor of 2 10 to 10 1 E 6 Measure e5505...

Страница 190: ...s click the Close button Selecting Loop Suppression Verification 1 Using Figure 136 on page 191 as a guide navigate to the Cal tab 2 In the Cal dialog box check Verify calculated phase locked loop suppression and Always Show Suppression Graph Select If limit is exceeded Show Loop Suppression Graph 3 When you have completed these operations click the Close button Figure 135 Selecting a reference so...

Страница 191: ... 8644B Use it to help you estimate if the measurement noise floor is below the expected noise level of your DUT Figure 136 Selecting loop suppression verification e5505a_user_select_loop 24 Jun 04 rev 3 Figure 137 Noise characteristics for the microwave measurement 10k 1k 100 10 1 10M 1M 100k 160 140 120 100 80 60 40 20 E5505a_noise_charac_microwave 26 Feb 04 rev 1 Specification Typical Offset fre...

Страница 192: ...ifier s noise will have on the measured noise floor Beginning the measurement 1 From the Measurement menu choose New Measurement See Figure 138 2 When the Do you want to perform a New Calibration and Measurement prompt appears click Yes 3 When the Connect Diagram dialog box appears click on the hardware drop down arrow and select your hardware configuration from the list See Figure 140 on page 193...

Страница 193: ...Figure 140 Connect diagram for the microwave source measurement e5505a_user_connect_free_osc 24 Jun 04 rev 3 TEST SET DOWNCONVERTER N5500A N5502A CAUTION The test set s signal input is subject to the limits and characteristics in Table 27 To prevent damage to the test set s hardware components do not apply the input signal to the test set s signal input connector until the input attenuator Option ...

Страница 194: ...and characteristics Limits Frequency 50 kHz to 1 6 GHz Std 50 kHz to 26 5 GHz Option 001 50 kHz to 26 5 GHz Option 201 Maximum Signal Input Power Sum of the reference and signal input power shall not exceed 23 dBm At Attenuator Output Operating Level Range RF Phase Detectors 0 to 23 dBm Signal Input 15 to 23 dBm Reference Input Microwave Phase Detectors 0 to 5 dBm Signal Input 7 to 10 dBm Referenc...

Страница 195: ...will require that you adjust the center frequency of one of the sources above and below the frequency of the other source until the beatnote appears on the oscilloscope s display If incrementing the frequency of one of the sources does not produce a beatnote you will need to verify the presence of an output signal from each source before proceeding See Figure 141 NOTE If the center frequencies of ...

Страница 196: ...Loop Suppression See Figure 142 on page 197 NOTE If you are able to locate the beatnote but it distorts and then disappears as you adjust it towards 0 Hz your sources are injection locking to each other Set the beatnote to the lowest frequency possible before injection locking occurs and then refer to Minimizing Injection Locking in the Problem Solving section of this chapter for recommended actio...

Страница 197: ...ical loop suppression c Theoretical suppression curve this is the predicted loop suppression based on the initial loop parameters defined selected for this particular measurement kphi kvco loop bandwidth filters gain etc d Adjusted theoretical suppression curve this is the new adjusted theoretical value of suppression for this measurement It is based on changing loop parameters in the theoretical ...

Страница 198: ...ser s Guide 6 Absolute Measurement Examples Figure 143 shows a typical phase noise curve for a microwave source Figure 143 Typical phase noise curve for a microwave source e5505a_user_typ_noise_curve_micro 24 Jun 04 rev 3 ...

Страница 199: ...dBm Test Set 600 E 6 Hz 600 E 6 Hz same as Carrier Source Frequency 16 dBm 40 E 3 Hz V 10 Volts 0 Volts 600 Ω 3 Cal Tab Phase Detector Constant VCO Tune Constant Phase Lock Loop Suppression If Limit is exceeded Measure Phase Detector Constant Calculate from expected VCO Tune Constant Verify calculated phase locked loop suppression Show Suppression Graph 4 Block Diagram Tab Carrier Source Downconve...

Страница 200: ...e 0 20 dBM 0 dBm 0 dB 0 dB Checked Microwave 0 to 26 5 GHz Unchecked 0 mA 10 MHz Unchecked 0 ppm v 0 ppm V 126 Hz 10000 Hz 7 Graph Tab Title Graph Type X Scale Minimum X Scale Maximum Y Scale Minimum Y Scale Maximum Normalize trace data to a Scale trace data to a new carrier frequency of Shift trace data DOWN by Trace Smoothing Amount Power present at input of DUT Microwave Source 12 GHz vs Agilen...

Страница 201: ...urement System User s Guide Agilent Technologies 7 Residual Measurement Fundamentals What is Residual Noise 202 Assumptions about Residual Phase Noise Measurements 204 Calibrating the Measurement 206 Measurement Difficulties 225 ...

Страница 202: ...ency which adds in a linear fashion to the signal See Figure 144 Multiplicative noise This noise has two known causes The first is an intrinsic direct phase modulation with a 1 f spectral density and the exact origin of this noise component is unknown The second in the case of amplifiers or multipliers is noise which may modulate an RF signal by the multiplication of baseband noise with the signal...

Страница 203: ...ndamentals 7 Agilent E5505A User s Guide 203 Figure 145 Multiplicative noise components Device under test E5505a_multi_noise_comp 27 Feb 04 rev 1 Source Noiseless source Base band noise Base band noise mixed around the signal ...

Страница 204: ...he AM component of the signal is greater than 20 to 30 dB above the residual phase noise it will contribute to the residual phase noise measurement and show the residual phase noise as being greater than it really is The DUT does not exhibit a bandpass filter function A bandpass filter type response will cause the source noise to be decorrelated at the edge of the filter This decorrelation of the ...

Страница 205: ...result or 3 dB less All that really can be concluded is that the noise level of one of the DUTs is at least 3 dB lower than the measured result at any particular offset frequency If a more precise determination is required at any particular offset frequency a third DUT must also be measured against the other two DUTs The data from each of the three measurements can then be processed by the phase n...

Страница 206: ...e noise measurements They are User Entry of Phase Detector Constant Measured DC Peak Beatnote Double Sided ΦM Spur Single Sided Spur The method used will mainly be determined by the sources and equipment available to you When calibrating the system for measurements remember that the calibration is only as accurate as the data input to the system software See Figure 148 Figure 148 General equipment...

Страница 207: ...ed to determine the delay difference At source noise shows up unattenuated At lower offsets source noise is attenuated at 20 dB per decade rate at 0 1 of source noise is attenuated 20 dB Examples of sources which best meet these requirements are the 8644B and 8642A B The source used for making residual phase noise measurements must be low in AM noise because source AM noise can cause AM to ΦM conv...

Страница 208: ...ases where the signal level out of the DUT is too small to drive the phase detector or the drive level is inadequate to provide a low enough system noise floor In this case the amplifier should have the following characteristics It should have the lowest possible noise figure and the greatest possible dynamic range The signal level must be kept as high as possible at all points in the setup to min...

Страница 209: ...est configuration Advantages Easy method for calibrating the measurement system Requires little additional equipment only an RF power meter to manually measure the drive levels into the phase detector or monitor oscilloscope Fastest method of calibration If the same power levels are always at the phase detector as in the case of leveled outputs the phase detector sensitivity will always be essenti...

Страница 210: ...f the graph This is the value you will enter as the Current Detector Constant when you define your measurement Note that the approximate measurement noise floor provided by the Signal Input port level is shown across the bottom of the graph Figure 149 Measuring power at phase detector signal input port Table 29 Acceptable amplitude ranges for the phase detectors Phase Detector 50 kHz to 1 6 GHz 1 ...

Страница 211: ...r to the Signal Input port 7 After you complete the measurement set up procedures and begin running the measurement the computer will prompt you to adjust for quadrature Figure 151 on page 212 Adjust the phase difference at the phase detector to 90 degrees quadrature by either adjusting the test frequency or by adjusting an optional variable phase shifter or line stretcher Quadrature is attained w...

Страница 212: ...drature e5505a_user_adjust_quad 24 Jun 04 rev 3 NOTE For the system to accept the adjustment to quadrature the meter must be within 2 mV to 4 mV Figure 152 Measuring power at phase detector reference input port Power splitter Phase detector Source E5505a_pwr_phase_det_ref 27 Feb 04 rev 1 Optional line stretcher Power meter or spectrum analyzer Test set Signal input Ref input ...

Страница 213: ...hase shifter or the frequency of the source An oscilloscope or voltmeter can optionally be used for setting the positive and negative peaks Disadvantages Has only moderate accuracy compared to the other calibration methods Does not take into account the amount of phase detector harmonic distortion relative to the measured phase detector gain hence the phase detector must operate in its linear regi...

Страница 214: ... for the Phase Detectors Phase Detector 50 kHz to 1 6 GHz 1 2 to 26 5 GHz1 1 Phase noise test Options 001 and 201 Ref Input L Port Signal Input R Port Ref Input L Port Signal Input R Port 15 dBm to 23 dBm 0 dBm to 23 dBm 7 dBm to 10 dBm 0 dBm to 5 dBm Power splitter Phase detector Source E5505a_connect_opt_oscillo 27 Feb 04 rev 1 Optional line stretcher Low pass filter Oscilloscope Test set Signal...

Страница 215: ...from the two sources For the system to calibrate the beatnote frequency must be within the following ranges shown in Table 31 Advantages Simple method of calibration Disadvantages It requires two RF sources separated by 0 1 Hz to 50 MHz at the phase detector The calibration source output power must be manually adjusted to the same level as the power splitter output it replaces requires a power met...

Страница 216: ...uency such that the beatnote frequency is within the range of the analyzers being used 6 The system can now measure the calibration constant 7 Disconnect the calibration source and reconnect the power splitter 8 Adjust the phase difference at the phase detector to 90 degrees quadrature either by adjusting the test frequency or by adjusting an Figure 154 Measuring power from splitter Table 32 Accep...

Страница 217: ...o calibrate the beatnote frequency must be within the following ranges shown in Table 33 NOTE For the system to accept the adjustment to quadrature the meter must be within 2 mV to 4 mV Figure 155 Calibration source beatnote injection Power splitter Phase detector Source RF calibration source E5505a_cali_source_beatnote 27 Feb 04 rev 1 Optional line stretcher Signal input Ref input 50Ω load Table ...

Страница 218: ...ouble Sided spur This calibration option has the following requirements One of the input frequency sources must be capable of being phase modulated The resultant sideband spurs from the phase modulation must have amplitudes that are 100 dB and 20 dB relative to the carrier amplitude The offset frequency or modulation frequency must be between 10 Hz and maximum See the Measured beatnote on page 215...

Страница 219: ...of the test set s phase detector Table 34 shows the acceptable amplitude ranges for the E5505A system phase detectors NOTE Because the calibration is performed under actual measurement conditions the Double sided Spur Method and the Single sided Spur Method are the two most accurate calibration methods NOTE Most phase modulators are typically narrow band devices therefore a wide range of test freq...

Страница 220: ...ed port This level is necessary to prevent cancellation of the modulation in the phase detector Cancellation would result in a smaller phase detector constant or a measured noise level that is worse than the Table 34 Acceptable amplitude ranges for the phase detectors Phase Detector 50 kHz to 1 6 GHz 1 2 to 26 5 GHz1 1 Phase noise test set options 001 and 201 Ref Input L Port Signal Input R Port R...

Страница 221: ... measure the phase detector constant by pressing Y to proceed 11 Remove audio source 12 Reset quadrature and measure phase noise data Single Sided spur This calibration option has the following requirements A third source to generate a single sided spur An external power combiner or directional coupler to add the calibration spur to the frequency carrier under test The calibration spur must have a...

Страница 222: ...ctions Note that the input signal into the directional coupler is being supplied to the coupler s output port 2 Measure the power level that will be applied to the Signal Input port of the test set s phase detector Table 35 on page 223 shows the acceptable amplitude ranges for the E5505A system phase detectors NOTE The Single sided Spur Method and the Double sided Spur Method Option 4 are the two ...

Страница 223: ...t in a smaller phase detector constant or a measured noise level that is worse than the actual performance The isolation level is set by the port to port isolation of the power splitter and the isolation of the 20 dB coupler This isolation can be improved at the expense of signal level by adding an attenuator between the coupler and the power splitter Table 35 Acceptable Amplitude Ranges for the P...

Страница 224: ...r scale 7 Enter sideband level and offset 8 Check quadrature and measure the phase detector constant 9 Remove audio source 10 Reset quadrature and measure phase noise data Figure 161 Carrier to spur ratio of non modulated signal Power splitter Phase detector Source E5505a_carrier_spur_ratio_non_mod 01 Mar 04 rev 1 Optional line stretcher Test set Signal input Ref input 60 dBc RF spectrum analyzer ...

Страница 225: ...uipment connected until the measurements have been made all problems corrected and the results have been evaluated to make sure that the measurement is valid If the equipment is disconnected before the results have been fully evaluated it may be difficult to troubleshoot the measurement System connections The first thing to check if problems occur is the instrument connections and settings as this...

Страница 226: ...226 Agilent E5505A User s Guide 7 Residual Measurement Fundamentals ...

Страница 227: ...227 E5505A Phase Noise Measurement System User s Guide Agilent Technologies 8 Residual Measurement Examples Amplifier Measurement Example 228 ...

Страница 228: ...r test Power splitter NARDA 30183 Coaxial cables and adapters necessary to connect the DUT and reference source to the test set The setup for a residual phase noise measurement uses a phase shifter to set quadrature at the phase detector See Figure 162 on page 229 CAUTION To prevent damage to the test set s components do not apply the input signal to the signal input connector until the input atte...

Страница 229: ...ose res_noise_1ghz_demoamp pnm See Figure 163 4 Click the Open button Figure 162 Setup for residual phase noise measurement Power splitter Phase detector Source E5505a_user_connect_osc_vol_peak 16 Mar 04 rev 3 DUT Test set Signal input Ref input Optional line stretcher Low pass filter Oscilloscope Connect scope to monitor port Figure 163 Select the parameters definition file e5505a_user_select_par...

Страница 230: ...he Define menu choose Measurement then choose the Type and Range tab from the Define Measurement window 6 From the Measurement Type pull down select Residual Phase Noise without using phase lock loop See Figure 164 7 Choose the Sources tab from the Define Measurement window 8 Enter the carrier center frequency of your DUT Enter the same frequency for the detector input frequency See Figure 165 on ...

Страница 231: ...fine Measurement window 10 Select Derive detector constant from measured DC peak voltage as the calibration method See Figure 166 Figure 165 Enter frequencies into source tab Figure 166 Select constant in the cal tab e5505a_enter_freq 27 jun 04 rev 3 e5505a_user_select_constant_tab 24 Jun 04 rev 3 ...

Страница 232: ...own select Manual b From the Phase Detector pull down select Automatic Detector Selection 12 Choose the Graph tab from the Define Measurement window 13 Enter a graph description of your choice E5500 Residual Phase Noise Measurement 1 GHz for example See Figure 168 on page 233 Figure 167 Select parameters in the block diagram tab e5505a_user_select_param_blk_dia_tab 24 Jun 04 rev 3 ...

Страница 233: ...g BNC cables may degrade the close in phase noise results and while adequate for this example should not be used for an actual measurement on an unknown device unless absolutely necessary Measurement environment The low noise floors typical of these devices may require that special attention be given to the measurement environment The following precautions will help ensure reliable test results Fi...

Страница 234: ...e View menu choose Meter to select the quadrature meter See Figure 169 1 From the Measurement menu choose New Measurement See Figure 170 Figure 169 Select meter from view menu Figure 170 Selecting New Measurement e5505a_user_select_meter_view_menu 24 Jun 04 rev 3 E5500_new_measurement 04 Apr 04 rev 1 ...

Страница 235: ...ion from the pull down list Refer to Figure 172 4 Connect your DUT and reference sources to the test set at this time Confirm your connections as shown in the appropriate connect diagram The input attenuator Option 001 only is now correctly configured based on your measurement definition Figure 171 Confirm new measurement Figure 172 Setup diagram for the 8349A amplifier measurement example E5500_n...

Страница 236: ... to 26 5 GHz Option 201 Maximum Signal Input Power Sum of the reference and signal input power shall not exceed 23 dBm 30 dBm for Option 001 At Attenuator Output Operating Level Range RF Phase Detectors 0 to 23 dBm Signal Input 15 to 23 dBm Reference Input Microwave Phase Detectors 0 to 5 dBm Signal Input 7 to 10 dBm Reference Input Characteristics Input Impedance 50 Ωnominal NOTE Refer to the fol...

Страница 237: ...lied to the Signal Input port of the test set phase detector Table 37 shows the acceptable amplitude ranges for the test set phase detectors Table 37 Acceptable amplitude ranges for the phase detectors Phase Detector 50 kHz to 1 6 GHz 1 2 to 26 5 GHz1 1 Phase Noise Test Set Options 001 and 201 Ref Input L Port Signal Input R Port Ref Input L Port Signal Input R Port 15 dBm to 23 dBm 0 dBm to 23 dB...

Страница 238: ...REF INPUT ERR ACT STATUS SRQ TLK LSN GPIB RMT NOISE 0 01 Hz 100MHz 1 V Pk 50 50kHz 1600 MHz INPUT SIGNAL POSSIBLE SIGNAL INPUT 100MHz 50 23dBm 50kHz 1600MHz MAXIMUM POWER 30dBm OUTPUT POWER POWER N5500A Test Set Spectrum analyzer Digitizer input Digitizer output GPIB Display PC Calibration source DUT Power splitter Phase shifter Delay line Test set To test set rear panel CHIRP input Power splitter...

Страница 239: ...ng an internal voltmeter The quadrature meter s digital display can be used to find the peak The phase may be adjusted either by varying the frequency of the source or by adjusting a variable phase shifter or line stretcher 6 The system software will then prompt you to set the phase noise software s meter to quadrature by adjusting the phase shifter until the meter indicates 0 volts then press Con...

Страница 240: ...e been taken over the entire range you specified in the Measurement definition s Type and Range When the measurement is complete When the measurement is complete refer to Chapter 14 Evaluating Your Measurement Results for help in evaluating your measurement results Figure 177 on page 241 shows a typical phase noise curve for an RF Amplifier Figure 176 Adjust phase shifter until meter indicates 0 v...

Страница 241: ...ent example Step Parameters Data 1 Type and Range Tab Measurement Type Start Frequency Stop Frequency Minimum Number of Averages FFT Quality Swept Quality Residual Phase Noise without using a phase locked loop 10 Hz 100 E 6 Hz 4 Normal Fast 2 Sources Tab Carrier Source Frequency Power Detector Input Frequency 1 E 9 Hz 10 dBm 1 E 9 Hz e5505a_user_adjust_dif_phase 24 Jun 04 rev 3 ...

Страница 242: ...Integrator Attenuation 0 dB 20 MHz Auto checked Auto Gain Minimum Auto Gain 14 dB Not checked 0 dBm 6 Dowconverter Tab The downconverter parameters do not apply to this measurement example 7 Graph Tab Title Graph Type X Scale Minimum X Scale Maximum Y Scale Minimum Y Scale Maximum Normalize trace data to a Scale trace data to a new carrier frequency of Shift trace data DOWN by Trace Smoothing Amou...

Страница 243: ...243 E5505A Phase Noise Measurement System User s Guide Agilent Technologies 9 FM Discriminator Fundamentals The Frequency Discriminator Method 244 ...

Страница 244: ...le Basic theory The delay line implementation of the frequency discriminator Figure 178 converts short term frequency fluctuations of a source into voltage fluctuations that can be measured by a baseband analyzer The conversion is a two part process first converting the frequency fluctuations into phase fluctuations and then converting the phase fluctuations to voltage fluctuations The frequency f...

Страница 245: ...ded by the delay line and is the frequency offset from the carrier that the phase noise measurement is made System sensitivity A frequency discriminator s system sensitivity is determined by the transfer response As shown below it is desirable to make both the phase detector constant and the amount of delay large so that the voltage fluctuations out of a frequency discriminator will be measurable ...

Страница 246: ... to carrier than a 50 ns delay line but will not be usable beyond 2 5 MHz offsets without compensating for the sin x x response the 50 ns line is usable to offsets of 10 MHz Increasing the delay also increases the attenuation of the line While this has no direct effect on the sensitivity provided by the delay line it does reduce the signal into the phase detector and can result in decreased and de...

Страница 247: ...sults in LZ 8 7 dB of attenuation The optimum sensitivity of a system with the phase detector operating out of results from using a length of coaxial line that has 8 7 dB of attenuation One way to increase the sensitivity of the discriminator when the phase detector is out of compression is to increase the signal into the delay line This can be accomplished with an RF amplifier before the signal s...

Страница 248: ...r by using a more efficient line so that the signal level out is 5 7 dBm or 8 7 dB below the mixer compression point Careful delay line selection is crucial for good system sensitivity In cases where the phase detector is operating out of compression sensitivity can be increased by using a low loss delay line or by amplifying the signal from the DUT Because attenuation in coaxial lines is frequenc...

Страница 249: ...System User s Guide Agilent Technologies 10 FM Discriminator Measurement Examples Introduction 250 FM Discriminator Measurement using Double Sided Spur Calibration 251 Discriminator Measurement using FM Rate and Deviation Calibration 267 ...

Страница 250: ...iminator measurement uses a delay line to convert frequency fluctuations to phase fluctuations and a phase shifter to set quadrature at the phase detector In the Discriminator measurement the source is placed ahead of the power splitter One output of the splitter feeds a delay line with enough delay to decorrelate the source noise The delay line generates a phase shift proportional to the frequenc...

Страница 251: ...vel at the output of the delay line of between 5 and 17 ICBM Be sure to take into account an additional 4 to 6 dB of loss in the power splitter The loss across 8 feet of BNC cable specified in this example is negligible The test set Signal and Reference inputs requires 15 ICBM CAUTION To prevent damage to the test set s components do not apply the input signal to the signal input connector until t...

Страница 252: ...red 3 In the File Name box choose vco_dss pnm See Figure 182 4 Click the Open button Figure 181 Discriminator noise floor as a function of delay time 10M 100M 100 10 1 1 01 1M 100K 10K 1K 180 0 20 40 20 40 60 80 100 120 140 160 E5505a_disc_noise_floor 01 Mar 04 rev 1 10nS 100nS 1µS L f dBc Hz vs f Hz Figure 182 Select the parameters definition file e5505a_user_select_param_def_file_vco_dss 25 Jun ...

Страница 253: ... that has been entered for the FM discriminator measurement example 5 From the Define menu navigate to the Measurement window Using Figure 183 as a guide a Choose the Type and Range tab from the Define Measurement window b From the Measurement Type pull down in Type and Range tab select Absolute Phase Noise using an FM discriminator Figure 183 Select measurement type e5505a_user_select_measurement...

Страница 254: ...r as the calibration method b Feed the output from a modulated calibration source into a spectrum analyzer and measure the 1st modulation sideband frequency and power relative to the carrier s frequency and power Enter the parameters in the following step c Set the Know Spur Parameters Offset Frequency and Amplitude for the spur you plan to use for calibration purposes This calibration method requ...

Страница 255: ... Diagram tab from the Define Measurement window a From the Reference Source pull down select Manual b From the Phase Detector pull down select Automatic Detector Selection See Figure 186 on page 256 Figure 185 Enter parameters into the call tab e5505a_user_enter_param_call_tab 25 Jun 04 rev 2 ...

Страница 256: ...the Define Measurement window 10 Enter a graph description of your choice See Figure 187 Figure 186 Select parameters in the block diagram tab Figure 187 Select Graph Description on Graph Tab e5505a_user_select_param_blk_diag_tab2 25 Jun 04 rev 2 e5505a_user_select_graph_desc_graph_tab 25 Jun 04 rev 3 ...

Страница 257: ...cause they are more widely available Using BNC cables may degrade the close in phase noise results and while adequate for this example should not be used for an actual measurement on an unknown device unless absolutely necessary Measurement environment The low noise floors typical of these devices may require that special attention be given to the measurement environment The following precautions ...

Страница 258: ...the View menu choose Meter to select the quadrature meter See Figure 188 12 From the Measurement menu choose New Measurement See Figure 189 Figure 188 Select meter from view menu Figure 189 Selecting New Measurement e5505a_user_select_meter_view_menu2 25 Jun 04 rev 2 E5500_new_measurement 04 Apr 04 rev 1 ...

Страница 259: ... Yes 14 When the Connect Diagram dialog box appears click on the hardware pull down arrow and select your hardware configuration from the list See Figure 191 Figure 190 Confirm new measurement Figure 191 Setup diagram for the FM discrimination measurement example E5500_new_cali_meas 04 Apr 04 rev 1 e5505a_user_setup_diag_FM_dis_ex 25 Jun 04 rev 3 TEST SET N5500A ...

Страница 260: ... occurs at the connection diagram Table 41 Test Set Signal Input Limits and Characteristics Limits Frequency 50 kHz to 1 6 GHz Std 50 kHz to 26 5 GHz Option 001 50 kHz to 26 5 GHz Option 201 Maximum Signal Input Power Sum of the reference and signal input power shall not exceed 23 dBm At Attenuator Output Operating Level Range RF Phase Detectors 0 to 23 dBm Signal Input 15 to 23 dBm Reference Inpu...

Страница 261: ...er_connect_diag_ex 25 Jun 04 rev 3 23dBm 50kHz 1600MHz MAXIMUM POWER 20mA MAX TUNE VOLTAGE OUT OF LOCK 100kHz ANALYZER ANALYZER RF ANALYZER PHASE DET OUTPUT MONITOR 15 dBm MIN 50kHz 1600 MHz REF INPUT ERR ACT STATUS SRQ TLK LSN GPIB RMT NOISE 0 01 Hz 100MHz 1 V Pk 50 50 kHz 1600 MHz INPUT SIGNAL POSSIBLE SIGNAL INPUT 100MHz 50 23dBm 50kHz 1600MHz MAXIMUM POWER 30dBm OUTPUT POWER POWER N5500A Test ...

Страница 262: ...les 2 Establish quadrature by adjusting the phase shifter until the meter indicates 0 volts then press Continue Figure 193 Calibration measurement 1 of 5 Figure 194 Calibration measurement 2 of 5 35505a_cal_measure1 21 jun 04 rev1 e5505a_user cal_measure2 25 Jun 04 rev 2 ...

Страница 263: ...h quadrature and continue the measurement The segment data will be displayed on the computer screen as the data is taken until all segments have been taken over the entire range you specified in the Measurement definition s Type and Range Figure 195 Calibration measurement 3 of 5 Figure 196 Calibration measurement 4 of 5 Figure 197 Calibration measurement 5 of 5 e5505a_user cal_measure3 25 Jun 04 ...

Страница 264: ...ement Results for help in evaluating your measurement results If the test system has problems completing the measurement it will inform you by placing a message on the computer display Figure 198 shows a typical absolute measurement using FM discrimination Figure 198 Typical phase noise curve using double sided spur calibration e5505a_user typ_noise_curve_spur_cal 25 Jun 04 rev 2 ...

Страница 265: ...ncy Power Carrier Source is Connected to Detector Input Frequency 1 027 E 9 Hz 19 dBm Test Set 1 027 E 9 Hz 3 Cal Tab FM Discriminator Constant Current Phase Detector Constant Know Spur Parameters Offset Frequency Amplitude Calibration Source Frequency Power Derive Constant from Double Sided Spur 82 25 E 9 20 E3 12 dBc 1 027 E 9 Hz 16 dBm 4 Block Diagram Tab Carrier Source Phase Shifter DUT in Pat...

Страница 266: ...cale Maximum Normalize trace data to a Scale trace data to a new carrier frequency of Shift trace data DOWN by Trace Smoothing Amount Power present at input of DUT FM Discrim 50 ns dly 1 027GHz 19 dBm out VCO DSS Single sideband Noise dBc Hz 10 Hz 100 E 6 Hz 10 dBc Hz 190 dBc Hz 1 Hz bandwidth 1 times the current carrier frequency 0 dB 0 0 dB Table 42 Parameter data for the double sided spur calib...

Страница 267: ...ars NOTE In order to use the FM rate and deviation calibration method you must have a signal source that is calibrated for FM modulation rate and FM deviation parameters All Agilent Technologies signal generators meet this requirement NOTE To ensure accurate measurements allow the DUT and measurement equipment to warm up at least 30 minutes before making the noise measurement Table 43 Required equ...

Страница 268: ...le 3 Determine the loss in the delay line Verify that the signal source will be able to provide a power level at the output of the delay line of between 5 and 17 ICBM Be sure to take into account an additional 4 to 6 dB of loss in the power splitter The loss across 8 feet of BNC cable specified in this example is negligible The test set Signal and Reference inputs requires 15 ICBM Defining the mea...

Страница 269: ...ered for the FM discriminator measurement example 5 From the Define menu choose Measurement then choose the Type and Range tab from the Define Measurement window 6 From the Measurement Type pull down select Absolute Phase Noise using an FM discriminator See Figure 201 Figure 200 Select the parameters definition file Figure 201 Select measurement type e5505a_user select_param_def_file_vco_rd 25 Jun...

Страница 270: ...me frequency for the detector input frequency See Figure 202 8 Choose the Cal tab from the Define Measurement window 9 Select Derive constant from FM rate and deviation as the calibration method 10 Set the FM Rate to 20 kHz and FM Deviation to 10 kHz which are the recommended FM rate and deviation See Figure 203 on page 271 Figure 202 Enter frequencies in Source tab e5505a_user_enter_source_tab 25...

Страница 271: ...iagram tab from the Define Measurement window See Figure 204 on page 272 a From the Reference Source pull down select Manual b From the Phase Detector pull down select Automatic Detector Selection Figure 203 Enter parameters into the Cal tab e5505a_user _enter_param_cal_tab8272e 25 Jun 04 rev 2 ...

Страница 272: ...Measurement Examples 12 Choose the Graph tab from the Define Measurement window 13 Enter a graph description of your choice See Figure 205 on page 273 Figure 204 Enter parameters in the Block Diagram tab e5505a_user _enter_param_diag_tab 25 Jun 04 rev 2 ...

Страница 273: ... may degrade the close in phase noise results and while adequate for this example should not be used for an actual measurement on an unknown device unless absolutely necessary Measurement environment The low noise floors typical of these devices may require that special attention be given to the measurement environment The following precautions will help ensure reliable test results Filtering on p...

Страница 274: ...the View menu choose Meter to select the quadrature meter See Figure 206 2 From the Measurement menu choose New Measurement See Figure 207 Figure 206 Select meter from the View menu Figure 207 Selecting New Measurement e5505a_user_select_meter_view_menu2 25 Jun 04 rev 2 E5500_new_measurement 04 Apr 04 rev 1 ...

Страница 275: ... Yes 4 When the Connect Diagram dialog box appears click on the hardware pull down arrow and select your hardware configuration from the list See Figure 209 Figure 208 Confirm new measurement Figure 209 Setup diagram for the FM Discrimination measurement example E5500_new_cali_meas 04 Apr 04 rev 1 e5505a_user_setup_diag_FM_dis_ex 25 Jun 04 rev 3 TEST SET N5500A ...

Страница 276: ...which occurs at the connection diagram Table 44 Test set signal input limits and characteristics Limits Frequency 50 kHz to 1 6 GHz Std 50 kHz to 26 5 GHz Option 001 50 kHz to 26 5 GHz Option 201 Maximum Signal Input Power Sum of the reference and signal input power shall not exceed 23 dBm At Attenuator Output Operating Level Range RF Phase Detectors 0 to 23 dBm Signal Input 15 to 23 dBm Reference...

Страница 277: ...a_user_connect_diag_ex 25 Jun 04 rev 3 23dBm 50kHz 1600MHz MAXIMUM POWER 20mA MAX TUNE VOLTAGE OUT OF LOCK 100kHz ANALYZER ANALYZER RF ANALYZER PHASE DET OUTPUT MONITOR 15 dBm MIN 50 kHz 1600 MHz REF INPUT ERR ACT STATUS SRQ TLK LSN GPIB RMT NOISE 0 01 Hz 100MHz 1V Pk 50 50kHz 1600 MHz INPUT SIGNAL POSSIBLE SIGNAL INPUT 100MHz 50 23dBm 50kHz 1600MHz MAXIMUM POWER 30dBm OUTPUT POWER POWER N5500A Te...

Страница 278: ...djusting the phase shifter until the meter indicates 0 volts then press Continue 3 Apply modulation to the carrier signal then press Continue Figure 211 Calibration measurement 1 of 5 Figure 212 Calibration measurement 2 of 5 35505a_cal_measure1 21 jun 04 rev1 e5505a_user cal_measure2 25 Jun 04 rev 2 ...

Страница 279: ...easurement The segment data will be displayed on the computer screen as the data is taken until all segments have been taken over the entire range you specified in the Measurement definition s Type and Range Figure 213 Calibration measurement 3 of 5 Figure 214 Calibration measurement 4 of 5 Figure 215 Calibration measurement 5 of 5 e5505a_user cal_measure3 25 Jun 04 rev 2 e5505a_cal_measure4 21 ju...

Страница 280: ...asurement results If the test system has problems completing the measurement it will inform you by placing a message on the computer display Figure 216 on page 280 shows a typical absolute measurement using FM discrimination Table 45 on page 281 contains the data stored in the parameter definition file Figure 216 Typical phase noise curve using rate and deviation calibration e5505a_user _typ_noise...

Страница 281: ...Hz 19 dBm Test Set 1 027 E 9 Hz 3 Cal Tab FM Discriminator Constant Current Phase Detector Constant Know Spur Parameters Offset Frequency Amplitude Calibration Source Frequency Power Frequency Modulation FM Rate FM Deviation Derive Constant from FM rate and deviation 82 25 E 9 1 E3 6 dBc 1 027 E 9 Hz 16 dBm 20 E 3 Hz 10 E 3 Hz 4 Block Diagram Tab Carrier Source Phase Shifter DUT in Path Phase Dete...

Страница 282: ...race data to a new carrier frequency of Shift trace data DOWN by Trace Smoothing Amount Power present at input of DUT FM Discrim 50 ns dly 1 027GHz 19 ICBM out VCO R D Single sideband Noise dBc Hz 10 Hz 100 E 6 Hz 10 dBc Hz 190 dBc Hz 1 Hz bandwidth 1 times the current carrier frequency 0 dB 0 0 dB Table 45 Parameter data for the rate and deviation calibration example continued Step Parameters Dat...

Страница 283: ...11 AM Noise Measurement Fundamentals AM Noise Measurement Theory of Operation 284 Amplitude Noise Measurement 285 Calibration and Measurement General Guidelines 289 Method 1 User Entry of Phase Detector Constant 290 Method 2 Double Sided Spur 294 Method 3 Single Sided Spur 299 ...

Страница 284: ...signal and the measured baseband signal is calculated Phase noise measurement In the case of small angle phase modulation 0 1 rad the modulation sideband amplitude is constant with increasing modulation frequency The phase detector gain can thus be measured at a single offset frequency and the same constant will apply at all offset frequencies In the case of calibrating with phase modulation sideb...

Страница 285: ...urement except the phase modulation must be replaced with amplitude modulation The AM noise measurement is a characterization of a source The residual AM noise of a DUT can only be made by using a source with lower AM noise then subtracting that AM noise from the measured output noise of the DUT The noise floor of this technique is the noise floor of the source AM noise measurement block diagrams ...

Страница 286: ...nverter DUT E5505a_noise_sys_block_n5509a 01 Mar 04 rev 1 AM detector Option K21 Noise input Test set DUT E5505a_noise_sys_block_n5507a 01 Mar 04 rev 1 Microwave downconverter Noise input AM noise output Test set Signal input Figure 221 AM detector schematic E5505a_am_detector_schemo 01 Mar 04 rev 1 K21 polarity switch 511 RF input AM detector output Diode detector 10n 2600 µF at 25V ...

Страница 287: ...he 70429A Option K21 N5500A Option 001 or N5507A prevents the DC voltage component of the demodulated signal from saturating the system s low noise amplifier LNA The value of this capacitor sets the lower frequency limit of the demodulated output Carrier feedthrough in the detector may be excessive for frequencies below a few hundred megahertz The LNA is protected from saturation by the internal f...

Страница 288: ...ut or internal AM detector The test set will not tolerate more than 2 mV DC Input without overloading the LNA A DC block must be connected in series after the AM Detector to remove the DC component The 70429A Option K21 is designed specifically for this purpose or the internal DC blocking filter in either the N5500A or N5507A may be used ...

Страница 289: ...or may degrade as power increases above 15 dBm Noise in the region of the detector is best measured with about 10 dBm of drive level The noise floor is best measured with about 20 dBm of drive level An amplifier must be used in cases where the signal level out of the DUT is too small to drive the AM detector or is inadequate to produce a low enough measurement noise floor In this case the amplifie...

Страница 290: ...ck method of estimating the equivalent phase detector constant Disadvantages It is the least accurate of the calibration methods It does not take into account the amount of power at harmonics of the signal Procedure 1 Using information shown in Figure 222 and Figure 223 on page 291 Connect the circuit and tighten all connections If the N5500A Option 001 or N5507A is available use one of the connec...

Страница 291: ...ret the results The measured data will be plotted as single sideband AM noise in dBc Hz Figure 223 AM noise calibration setup DUT Power meter or spectrum analyzer E5505a_am_noise_cal_setup 01 Mar 04 rev 1 NOTE The quadrature meter should be at zero volts due to the blocking capacitor at the AM detector s output Figure 224 AM detector sensitivity graph e5505a_user_AM_cal ai rev2 10 24 03 ...

Страница 292: ...ctor gain in the actual measurement configuration Super quick method of estimating the equivalent phase detector constant Disadvantages Has only moderate accuracy compared to the other calibration methods Procedure 1 Using Figure 225 and Figure 226 connect circuit and tighten all connections If the N5500A Option 001 or N5507A is available use one of the connection diagrams described in AM noise me...

Страница 293: ...and over the equivalent phase detector constant can then be read from the left side of the graph The measured data will be plotted as single sideband AM noise in dBc Hz 4 Measure noise data and interpret the results Figure 226 Modulation sideband calibration setup DUT E5505a_mod_sideband_cal 02 Mar 04 rev 1 AM detector Noise input Test set DVM or oscilloscope Diode voltage monitor output NOTE The ...

Страница 294: ...rement of AM sidebands is required Procedure 1 Connect circuit as shown in Figure 227 and tighten all connections If the N5500A Option 001 or N5507A is available use one of the connection diagrams described in AM noise measurement block diagrams on page 285 2 Measure the power which will be applied to the AM detector It must be between 0 and 23 dBm 3 Measure the carrier to sideband ratio of the AM...

Страница 295: ...nterpret the results NOTE The carrier to sideband ratio for AM is C sb C sb 20 percentAM 100 log 6dB Figure 228 Measuring the carrier to sideband ratio Figure 229 Measuring the calibration constant E5505a_meas_car_side_ratio 02 Mar 04 rev 1 Source Modulation analyzer DUT with AM E5505a_meas_cal_constant 02 Mar 04 rev 1 AM detector Noise input Test set NOTE The quadrature meter should be at zero vo...

Страница 296: ...If the AM modulation is not very accurate a modulation analyzer must be used to make manual measurement of the AM sidebands Procedure 1 Connect circuit as shown in Figure 230 and tighten all connections If the N5500A Option 001 or N5507A is available use one of the connection diagrams described in AM noise measurement block diagrams on page 285 2 Measure the power which will be applied to the AM d...

Страница 297: ... the source output with a modulation analyzer See Figure 232 4 Enter the carrier to sideband ratio and offset frequency then measure the calibration constant See Figure 233 5 Remove the AM source and reconnect the DUT 6 Measure noise data and interpret the results NOTE The carrier to sideband ratio for AM is C sb C b 20 percentAM 100 log 6dB Figure 232 Measuring carrier to sideband ratio Figure 23...

Страница 298: ...298 Agilent E5505A User s Guide 11 AM Noise Measurement Fundamentals NOTE The quadrature meter should be at zero volts due to the blocking capacitor at the AM detector s output ...

Страница 299: ... analyzer for manual measurement of the signal to spur ratio and spur offset Procedure 1 Connect circuit as shown in Figure 234 and tighten all connections If the N5500A Option 001 or N5507A is available use one of the connection diagrams described in AM noise measurement block diagrams on page 285 2 Measure the power which will be applied to the AM detector It must be between 0 and 23 dBm 3 Measu...

Страница 300: ...urce output 6 Measure noise data and interpret the results Figure 235 Measuring relative spur level Figure 236 Measuring detector sensitivity DUT E5505a_meas_relative_spur 02 Mar 04 rev 1 Calibration source 20 dB coupler RF spectrum analyzer 10 dB atten DUT E5505a_meas_detector_sen 02 Mar 04 rev 1 Calibration source AM detector Test set Noise input 10 dB attenuator 20 dB coupler NOTE The quadratur...

Страница 301: ...301 E5505A Phase Noise Measurement System User s Guide Agilent Technologies 12 AM Noise Measurement Examples AM Noise with N5500A Option 001 302 ...

Страница 302: ...uipment Required equipment This measurement requires an 8644B in addition to the phase noise test system and your DUT You also need the coaxial cables and adapters necessary to connect the DUT and reference source to the test set Figure 237 shows the configuration used for an AM noise measurement CAUTION To prevent damage to the test set s components do not apply the signal input connector until t...

Страница 303: ...the parameter data that has been entered for this measurement example 5 From the Define menu choose Measurement then choose the Type and Range tab from the Define Measurement window 6 From the Measurement Type pull down select AM Noise See Figure 239 on page 304 Figure 238 Select the parameters definition file e5505a_user_select_param_def_file_AM 27 Jun 04 rev 3 NOTE The amplitude of a source unde...

Страница 304: ...ne Measurement window 8 Enter the carrier center frequency of your DUT Enter the same frequency for the detector input frequency See Figure 240 on page 304 Figure 239 Navigate to AM noise Figure 240 Enter Frequencies in Source Tab e5505a_user_nav_AM_noise 27 Jun 04 rev 3 e5505a_enter_freq 23 jun 04 rev2 ...

Страница 305: ...about various calibration techniques refer to Chapter 11 AM Noise Measurement Fundamentals 11 Choose the Block Diagram tab from the Define Measurement window 12 From the Phase Detector pull down select AM Detector See Figure 242 Figure 241 Enter parameters into the cal tab Figure 242 Select parameters in the block diagram tab e5505a_user_enter_param_cal_tab60 07e 27 Jun 04 rev 3 e5505a_user_select...

Страница 306: ...he Graph tab from the Define Measurement window 14 Enter a graph description of your choice See Figure 243 15 When you have completed these operations click the Close button Figure 243 Select graph description on graph tab e5505a_user_select_graph_desc_graph_AM 27 Jun 04 rev 3 ...

Страница 307: ...perform a New Calibration and Measurement prompt appears click Yes 3 When the Connect Diagram dialog box appears click on the hardware drop down arrow and select your hardware configuration from the list See Figure 246 on page 308 Figure 244 Selecting a new measurement Figure 245 Confirm measurement dialog box E5500_new_measurement 04 Apr 04 rev 1 E5500_new_cali_meas 04 Apr 04 rev 1 ...

Страница 308: ...t definition Figure 246 Connect diagram for the AM noise measurement e5505a_user_connect_diag_AM_noise 27 Jun 04 rev 3 CAUTION The test set s signal input is subject to the limits and characteristics in Table 47 on page 309 To prevent damage to the test set s hardware components do not apply the input signal to the test set s signal input connector until the input attenuator Option 001 has been se...

Страница 309: ...xample 23 dBm 1 2 26 5GHz 10dBm 50kHz 1600 MHz MAXIMUM POWER 20mA MAX TO DOWNCONVERTER FROM DOWNCONVERTER TUNE VOLTAGE OUT OF LOCK 100 kHz ANALYZER ANALYZER RF ANALYZER PHASE DET OUTPUT MONITOR 15dBm MIN 50kHz 1600MHz 7dBm MIN 1 2 26 5GHz REF INPUT ERR ACT STATUS SRQ TLK LSN GPIB RMT NOISE 0 01Hz 100MHz 1V Pk 50 50kHz 26 5GHz INPUT SIGNAL POSSIBLE SIGNAL INPUT 0VDC MAX 100MHz 50 50kHz 1600 MHz 23d...

Страница 310: ...he computer screen after each frequency segment has been measured For more information about various calibration techniques refer to Chapter 11 AM Noise Measurement Fundamentals When the measurement is complete When the measurement is complete refer to Chapter 14 Evaluating Your Measurement Results for help with the results Figure 248 shows a typical AM noise curve Figure 248 Typical AM noise curv...

Страница 311: ...et 600 E 6 Hz 3 Cal Tab Detector Constant Known Spur Parameters Offset Frequency Amplitude Use internal automatic self calibration 1 Hz 130 dBc 4 Block Diagram Tab Source AM Detector Down Converter Manual Test Set AM Detector None 5 Test Set Tab Input Attenuation LNA Low Pass Filter LNA Gain Detector Maximum Input Levels Microwave Phase Detector RF Phase Detector AM Detector Ignore out of lock con...

Страница 312: ...o a Scale trace data to a new carrier frequency of Shift trace data DOWN by Trace Smoothing Amount Power present at input of DUT AM Noise Measurement of an RF Signal AM Noise dBc Hz 10 Hz 100E 6 Hz 0 dBc Hz 180 dBc Hz 1 Hz bandwidth 1 times the current carrier frequency 0 dB 0 0 dB Table 48 Parameter data for the AM noise using an N5500A Option 001 continued Step Parameters Data ...

Страница 313: ...Phase Noise Measurement System User s Guide Agilent Technologies 13 Baseband Noise Measurement Examples Baseband Noise with Test Set Measurement Example 314 Baseband Noise without Test Set Measurement Example 318 ...

Страница 314: ...n the File Name box choose BBnoise_with_testset pnm See Figure 249 4 Click the Open button The appropriate measurement definition parameters for this example have been pre stored in this file Table 49 on page 317 lists the parameter data that has been entered for this measurement example NOTE To ensure accurate measurements allow the DUT and measurement equipment to warm up at least 30 minutes bef...

Страница 315: ...m a New Calibration and Measurement prompt appears click Yes 3 When the Connect Diagram dialog box appears click on the hardware drop down arrow and select N5500A option 001 test set only configuration from the list See Figure 252 on page 316 Figure 250 Selecting a new measurement Figure 251 Confirm measurement dialog box E5500_new_measurement 04 Apr 04 rev 1 E5500_new_cali_meas 04 Apr 04 rev 1 ...

Страница 316: ...ue Figure 253 shows a typical phase noise curve for a baseband noise measurement using a test set Figure 252 Connect diagram dialog box e5505a_conn_diag_dialog rev 1 23 jun 04 Figure 253 Typical phase noise curve for a baseband using a test set measurement e5505a_user_typ_noise_curve_baseband 27 Jun 04 rev 3 ...

Страница 317: ...ck Diagram Tab Noise Source Test Set Noise Input 4 Test Set Tab Input Attenuation LNA Low Pass Filter LNA Gain DC Block PLL Integrator Attenuation 0 dB 20 MHz Auto checked Auto Gain Minimum Auto Gain 14 dB Not checked 0 dBm 5 Graph Tab Title Graph Type X Scale Minimum X Scale Maximum Y Scale Minimum Y Scale Maximum Normalize trace data to Scale trace data to a new carrier frequency of Shift trace ...

Страница 318: ...file you want is stored 3 In the File Name box choose BBnoise_without_testset_89410 pnm 4 Click the Open button The appropriate measurement definition parameters for this example have been pre stored in this file Table 50 on page 321 lists the parameter data in this file NOTE To ensure accurate measurements allow the DUT and measurement equipment to warm up at least 30 minutes before making the no...

Страница 319: ...form a New Calibration and Measurement prompt appears click Yes 3 The Instrument Connection dialog box appears See Figure 258 on page 320 At this time connect your DUT and an FFT analyzer with the system as shown in Figure 257 on page 320 Figure 255 Selecting a new measurement Figure 256 Confirm measurement dialog box E5500_new_measurement 04 Apr 04 rev 1 E5500_new_cali_meas 04 Apr 04 rev 1 ...

Страница 320: ...st set measurement is not represented in the diagrams Figure 259 on page 321 shows a typical phase noise curve for a baseband noise measurement without using a test set Table 50 on page 321 lists the parameter data for this measurement example Figure 257 Connect diagram for baseband without test set measurement Figure 258 Instrument connection dialog box e5505a_user_connect_diag_baseband_noTS ai r...

Страница 321: ...100 E 6 Hz 4 Normal 2 Cal Tab Gain preceding noise input 0 dB 3 Block Diagram Tab Noise Source Test Set Noise Input 5 Graph Tab Title Graph Type X Scale Minimum X Scale Maximum Y Scale Minimum Y Scale Maximum Normalize trace data to a Scale trace data to a new carrier frequency of Shift trace data DOWN by Trace Smoothing Amount Power present at input of DUT Baseband Noise without using a Test Set ...

Страница 322: ...322 Agilent E5505A User s Guide 13 Baseband Noise Measurement Examples ...

Страница 323: ...Measurement System User s Guide Agilent Technologies 14 Evaluating Your Measurement Results Evaluating the Results 324 Gathering More Data 328 Outputting the Results 329 Graph of Results 330 Omit Spurs 332 Problem Solving 335 ...

Страница 324: ...Result File is recommended for each measurement These steps provide an overview of the evaluation process Look for obvious problems on the graph such as discontinuity breaks Compare the graph against known or expected data If necessary gather additional data about the noise characteristics of the DUT Looking for obvious problems Some obvious problems on a graph are as follows Discontinuities or br...

Страница 325: ... test If you are testing a product for which published specifications exist compare the measurement results against the noise and spur characteristics specified for the product If the product is operating correctly the noise graph provided by the phase noise system should be within the noise limits specified for the product If the device is a prototype or breadboard circuit it may be possible to e...

Страница 326: ...cteristics specified for that source If you have obtained an actual measured noise curve for the reference source you are using you can use it to determine if your measurement results have been increased by the noise of the reference source To do this determine the difference in dB between the level of the results graph and that of the reference source Then use the graph shown in Figure 261 to det...

Страница 327: ... Guide 327 Figure 262 Measurement results and reference source noise 100 10 100K 10K 1K 0 20 120 140 40 160 60 80 100 E5505a_meas_results_ref_source 02 Mar 04 rev 1 L f dBc Hz vs f Hz Measured reference source noise 7 dB difference at 10 kHz Measurement results ...

Страница 328: ...ng on page 335 repeating the measurement after each change allows you to check the effect that the change has had on the total noise graph To repeat a measurement on the Measurement menu click Repeat Measurement See Figure 263 Doing more research If you are still uncertain about the validity of the measurement results it may be necessary to do further research to find other validating data for you...

Страница 329: ...User s Guide 329 Outputting the Results To generate a printed hardcopy of your test results you must have a printer connected to the computer Using a printer To print the phase noise graph along with the parameter summary data select File Print on the menu ...

Страница 330: ...System functions and then display the results The following functions are available to help you evaluate your results Marker on page 330 Omit Spurs on page 332 Parameter summary on page 333 Marker The marker function allows you to display the exact frequency and amplitude of any point on the results graph To access the marker function 1 On the View menu click Markers See Figure 264 2 To remove the...

Страница 331: ...Evaluating Your Measurement Results 14 Agilent E5505A User s Guide 331 Figure 265 Add and delete markers e5505a_user_add_delete_markers 24 Jun 04 rev 3 ...

Страница 332: ...isplay Preferences See Figure 266 2 In the Display Preferences dialog box uncheck Spurs See Figure 267 Click OK 3 The Graph will be displayed without spurs Figure 268 on page 333 To re display the spurs check Spurs in the Display Preferences dialog box Figure 266 Select display preferences Figure 267 Uncheck spurs e5505a_user_nav_display_pref 24 Jun 04 rev 3 e5505a_user_uncheck_spurs2 ai rev2 10 2...

Страница 333: ...the measurement parameter entries that were used for this measurement The parameter summary data is included when you print the graph 1 On the View menu click Parameter Summary Figure 269 Figure 268 Graph without spurs e5505a_user_graph_without_spurs2 27 Jun 04 rev 3 Figure 269 Navigate to parameter summary e5505a_user_nav_param_sum 24 Jun 04 rev 3 ...

Страница 334: ...ting Your Measurement Results 2 The Parameter Summary Notepad dialog box appears Figure 270 The data can be printed or changed using standard Notepad functionality Figure 270 Parameter summary notepad e5505a_user_param_sum_note 27 Jun 04 rev 3 ...

Страница 335: ... Action Break between segments where closely spaced spurs are resolved in one segment but not in the next Closely spaced spurs that are resolved in one sweep segment but not in the next can cause an apparent jump in the noise where they are not resolved Use the Real time Monitor to evaluate the noise spectrum at the break frequency on the graph To eliminate the break in the graph you may find it n...

Страница 336: ... the effective noise floor for detecting spurs is above the plotted 1 Hz bandwidth noise by the bandwidth correction factor Break at the upper edge of the segment below PLL Bandwidth 4 Accuracy degradation of more than 1 or 2 dB can result in a break in the graph at the internal changeover frequency between the phase detector portion of the measurement and the voltage controlled oscillator tune li...

Страница 337: ...e system the DUT and the reference source Typical system spurs are 120 dBc and they occur at the power line and system vibration frequencies in the range of from 25 Hz to 1 kHz and above 10 MHz If you do not have a plot of the system s noise and spur characteristics perform the system Noise Floor Test If you suspect that the DUT or the reference source may be the spur source check each source usin...

Страница 338: ...t of potential spur sources is long and varied Many times the spur will not be at the fundamental frequency of the source but may be a harmonic of the source signal Some typical causes of electrical spurs are power lines radio broadcasting stations computers and computer peripherals any device that generates high frequency square waves and sum and difference products of oscillators that are not is...

Страница 339: ...05A User s Guide 339 Figure 271 L f Is only valid for noise levels below the small angle line 10M 40M 100 10 1 1M 100K 10K 1K 0 20 40 20 40 60 80 100 120 140 160 E5505a_valid_noise_levels 02 Mar 04 rev 1 L f dBc Hz vs f Hz Small angle phase noise limit ...

Страница 340: ...340 Agilent E5505A User s Guide 14 Evaluating Your Measurement Results ...

Страница 341: ... Guide Agilent Technologies 15 Advanced Software Features Introduction 342 Phase Lock Loop Suppression 343 Ignore Out Of Lock Mode 346 PLL Suppression Verification Process 347 Blanking Frequency and Amplitude Information on the Phase Noise Graph 353 ...

Страница 342: ...unctions allows you to manipulate the test system or to customize a measurement using the extended capabilities of the E5500 software This chapter describes each of these advanced functions Agilent recommends that only users who understand how the measurement and the test system are affected by each function use the Advanced Functions feature ...

Страница 343: ...parameters are displayed along with the PLL Suppression Curve PLL gain change This is the amount of gain change required to fit the Theoretical Loop Suppression curve to the measured loop suppression A PLL Gain Change of greater than 1 dB creates an accuracy degradation ACCY DEGRADED error If an accuracy degradation is detected the amount of error is determined from either the PLL Gain Change or t...

Страница 344: ...h high close in noise The PTR displayed should be approximately equal to the product of the VCO Tune Constant times the Tune Range of VCO This is not the case when a significant accuracy degradation is detected 4 dB by the Loop Suppression Verification In this case the PTR and Assumed Pole are adjusted when fitting the Theoretical Loop Suppression to the smoothed measured Loop Suppression and the ...

Страница 345: ... determines the Agilent E5505A system noise floor exclusive of the reference source VCO CONSTANT is the VCO Tune Constant used for the measurement The accuracy of the VCO Tune Constant determines the accuracy of the PLL noise measurement for offset frequencies in segments where the entire plotted frequency range is less than the PLL BW 4 The accuracy of the VCO Tune Constant is verified if the PLL...

Страница 346: ...se in noise that normally would cause an out of lock condition and stop the measurement When Ignore Out Of Lock is selected the user is responsible for monitoring phase lock This can be accomplished using an oscilloscope connected to the test set Aux Monitor port to verify the absence of a beatnote and monitor the dc output level When Ignore Out Of Lock is selected the test system does not verify ...

Страница 347: ... system controlled RF signal generator then the need to select PLL suppression verification is minimal To verify PLL suppression a stimulus source is required for the FFT analyzer This stimulus signal is connected to the CHIRP INPUT port on the rear panel of the test set The PC digitizer when used as the FFT analyzer provides a companion D A output for this purpose When an Agilent 89410A vector si...

Страница 348: ...oop suppression c Theoretical suppression curve Figure 276 on page 349 this is the predicted loop suppression based on the initial loop parameters defined selected for this particular measurement kphi kvco loop bandwidth filters gain etc d Adjusted theoretical suppression curve Figure 277 on page 350 through Figure 279 on page 351 this is the new adjusted theoretical value of suppression for this ...

Страница 349: ...eatures 15 Agilent E5505A User s Guide 349 Figure 275 Smoothed loop suppression curve Figure 276 Theoretical loop suppression curve e5505a_user_smoothed_loop_sup ai rev2 10 24 03 e5505a_user_theo_loop_sup ai rev2 10 24 03 ...

Страница 350: ... Software Features Figure 277 Smoothed vs theoretical loop suppression curve Figure 278 Smoothed vs Adjusted theoretical loop suppression curve e5505a_user_theo_vs_smoothe_loop_sup ai rev2 10 24 03 e5505a_user_smooth_vs_adj_theo ai rev2 10 24 03 ...

Страница 351: ...Advanced Software Features 15 Agilent E5505A User s Guide 351 Figure 279 Adjusted theoretical vs theoretical loop suppression curve e5505a_user_adj_theo_vs_theo ai rev2 10 24 03 ...

Страница 352: ...loop suppression in the frequency range plotted for the smoothed measured loop suppression The frequency of the assumed pole is normally much greater than the Closed PLL BW and there is no loop peaking If the smoothed measured PLL suppression shows peaking the assumed pole is shifted down in frequency to simulate the extra phase shift that caused the peaking If the peaking is really due to a singl...

Страница 353: ... secured levels described in this section is not reversible Once the frequency or frequency amplitude data has been blanked it can not be recovered If you need a permanent copy of the data you can print out the graph and parameter summary before you secure the data and store the printed data to a secured location NOTE An alternate method of storing classified data is to save the measurement test f...

Страница 354: ... all data is viewable is selected all frequency and amplitude information is displayed on the phase noise graph See Figure 281 and Figure 282 Figure 281 Choosing levels of security Figure 282 Unsecured all data is viewable e5505a_user_choose_security 27 Jun 04 rev 3 e5505a_user_unsecured_all 27 Jun 04 rev 3 ...

Страница 355: ...requencies cannot be viewed is selected all frequency information is blanked on the phase noise graph See Figure 283 through Figure 285 Figure 283 Choosing levels of security Figure 284 Secured frequencies cannot be found 1 e5505a_user_choose_security2 27 Jun 04 rev 3 e5505a_user_secured_not_found 27 Jun 04 rev 3 ...

Страница 356: ...ncies and Amplitudes cannot be viewed is selected all frequency and amplitude information is blanked on the phase noise graph See Figure 286 and Figure 287 Figure 285 Secured frequencies cannot be found 2 Figure 286 Choosing levels of security e5505a_user_secured_not_found2 27 Jun 04 rev 3 e5505a_user_choose_security3 27 Jun 04 rev 3 ...

Страница 357: ...Advanced Software Features 15 Agilent E5505A User s Guide 357 Figure 287 Secured frequencies and amplitudes cannot be viewed e5505a_user_secured_freq_amp_not_viewed 27 Jun 04 rev 3 ...

Страница 358: ...358 Agilent E5505A User s Guide 15 Advanced Software Features ...

Страница 359: ...crease in Measured Noise as Ref Source Approaches DUT Noise 363 Approximate Sensitivity of Delay Line Discriminator 364 AM Calibration 365 Voltage Controlled Source Tuning Requirements 366 Tune Range of VCO for Center Voltage 367 Phase Lock Loop Bandwidth vs Peak Tuning Range 369 Noise Floor Limits Due to Peak Tuning Range 370 8643A Frequency Limits 372 8644B Frequency Limits 375 8664A Frequency L...

Страница 360: ... port signal levels from 15 dBm to 15 dBm These estimates of sensitivity assume the signal level at the L port is appropriate for either the microwave or the RF mixer that is used 7 dBm or 15 dBm respectively The approximate phase detector calibration constant that results from the input signal level at the R port is shown on the right side of the graph Figure 288 Noise floor for R input port 140 ...

Страница 361: ...the power in the higher order sidebands of the phase modulation is still insignificant compared to the power in the first order sideband which ensures the calculation of L f is still valid As shown in Figure 289 the line plot of L f is correct above the line L f is increasingly invalid and Sφ f must be used to represent the phase noise of the signal Sφ f is valid both above and below the line When...

Страница 362: ... reference sources at specific frequencies Depending on the sensitivity that is required at the offset to be measured a single reference source may suffice or several different references may be needed to achieve the necessary sensitivity at different offsets Figure 290 Noise level for various reference sources E5505a_user_phase_noise_levels 17 Mar 04 rev 3 8657A B 8644B ESG with Opt 1E5 8664A 65A...

Страница 363: ... approaches the noise level of the DUT the level measured by the software which is the sum of all sources affecting the test system is increased above the actual noise level of the DUT Figure 291 Reference source and DUT noise levels 15 10 5 4 3 2 1 0 5 1 0 1 5 2 0 2 5 3 0 E5505a_inc_meas_noise 26 Feb 04 rev 1 Amount expected DUT noise exceeds reference noise dB Increase in measured noise due to r...

Страница 364: ...ity graphs indicate the delay line frequency discriminator can be used to measure some types of sources with useful sensitivity Longer delay lines improve sensitivity but eventually the loss in the delay line will exceed the available power of the source and cancel any further improvement Also longer delay lines limit the maximum offset frequency that can be measured Figure 292 Delay line discrimi...

Страница 365: ...alent phase Detector Constant from the measured AM Detector input level or from the diode detector s DC voltage The equivalent phase detector constant phase slope is read from the left side of the graph while the approximate detector input power is read from the right side of the graph Figure 293 AM detector sensitivity e5505a_user_AM_cal ai rev2 10 24 03 ...

Страница 366: ...haved and the VCO Tune Constant remains accurate After phase lock is established the test system monitors the tuning voltage required to maintain lock If the tuning voltage exceeds 5 of the PTR during the measurement the test system again informs the user and requests the oscillator be retuned or the problem be otherwise corrected before proceeding with the measurement These limits have been found...

Страница 367: ...tlines the minimum to maximum Tune Range of VCO that the software provides for a given center voltage The Tune range of VCO decreases as the absolute value of the center voltage increases due to hardware limitations of the test system Figure 295 Tune range of VCO for center voltage e5505a_user_peak_tune_range ai rev2 10 24 03 ...

Страница 368: ...typical phase noise level of a variety of sources and the minimum tuning range that is necessary for the test system to create a phase lock loop of sufficient bandwidth to make the measurement Sources with higher phase noise require a wider Peak Tuning Range Figure 296 Typical source noise level vs minimum tuning range e5505a_user_peak_tune_range ai rev2 10 24 03 ...

Страница 369: ...dwidth PLL BW chosen by the test system as a function of the Peak Tuning Range of the source Knowing the approximate closed PLL BW allows you to verify that there is sufficient bandwidth on the tuning port and that sufficient source isolation is present to prevent injection locking Figure 297 PLL BW vs peak tuning range e5505a_user_phase_band_peak_tune_range ai rev2 10 24 03 ...

Страница 370: ... 298 illustrates the equivalent phase noise at the Peak Tuning Range entered for the source due to the inherent noise at the test set Tune Voltage Output port A Tune Range of VCO 10 V and phase Detector Constant of 0 2V Rad is assumed Figure 298 Noise at source s peak tuning range e5505a_user_noise_floor_peak ai rev2 10 28 03 ...

Страница 371: ...n 0 0 10 10 1E 6 1 k 8662 600 8663 Measure Calculate Calculate Agilent 8642A B FM Deviation 0 10 600 Calculate Agilent 8643A 44B FM Deviation 0 10 600 Calculate Agilent 8664A Agilent 8665A B FM Deviation 0 5 See Caution Below 600 Calculate Other Signal Generator DCFM Calibrated for 1V FM Deviation 0 10 Rin Calculate Other User VCO Source Estimated within a factor of 2 10 to 10 See Tune Range of VC...

Страница 372: ...ow to access special functions on page 373 Model Number Option Band Minimum MHz Band Maximum MHz Mode 22 2 The 8643A defaults to Mode 2 operation Mode 13 3 Wideband FM Use Special Function 125 refer to How to access special functions on page 373 8643A 002 1030 2060 2000000 20000000 8643A 002 515 1029 99999999 1000000 10000000 8643A Standard 515 1030 1000000 10000000 8643A Both 257 5 514 99999999 5...

Страница 373: ...is special function allows you to have the instrument synthesize the FM signal in a digitized or linear manner Digitized FM is best for signal tone modulation and provides very accurate center frequency at low deviation rates Linear FM is best for multi tone modulation and provides a more constant group delay than the Digitized FM Table 57 Operating characteristics for 8643A modes 1 2 and 3 Charac...

Страница 374: ...function which allows you to turn on wide FM deviation The 8643 defaults to Mode 2 operation Wide FM deviation provides the maximum FM deviation and minimum RF output switching time In this mode the maximum deviation is increased by a factor of 10 to 10 MHz for a 1 GHz carrier The noise level of the generator is also increased in this mode however ...

Страница 375: ...ccount limited tuning resolution available in linear FM Special Function 120 refer to How to access special functions on page 373 Model Number Option Band Minimum MHz Band Maximum MHz Mode 3 Mode 2 Mode 1 8644B 002 1030 2060 200000 2000000 20000000 8644B 002 515 1029 99999999 100000 1000000 10000000 8644B Standard 515 1030 100000 1000000 10000000 8644B Both 257 5 514 99999999 50000 500000 5000000 ...

Страница 376: ...key to terminate data entries that do not require specific units kHz mV rad for example Example Special 1 2 0 ON Enter Table 59 Operating characteristics for 8644B modes 1 2 and 3 Characteristic Synthesis Mode Mode 1 Mode 2 Mode 3 RF Frequency Switching Time 90 ms 200 ms 350 ms FM Deviation at 1 GHz 10 MHz 1 MHz 100 kHz Phase Noise 20 kHz offset at 1 GHz 120 dBc 130 dBc 136 dBc Figure 300 8644B sp...

Страница 377: ...cial function allows you to have the instrument synthesize the FM signal in a digitized or linear manner Digitized FM is best for signal tone modulation and provides very accurate center frequency at low deviation rates Linear FM is best for multi tone modulation and provides a more constant group delay than the Digitized FM ...

Страница 378: ...nction 120 refer to How to access special functions on page 373 Model Number Option Band Minimum MHz Band Maximum MHz Mode 3 Mode 2 8664A 2060 3000 400000 10000000 8664A 1500 2059 99999999 200000 10000000 8664A 1030 1499 99999999 200000 5000000 8664A 750 1029 99999999 100000 5000000 8664A 515 749 99999999 100000 2500000 8664A 375 514 99999999 50000 2500000 8664A 257 5 374 99999999 50000 1250000 86...

Страница 379: ...nits kHz mV rad for example Example Special 1 2 0 ON Enter Description of special functions 120 120 FM synthesis This special function allows you to have the instrument synthesize the FM signal in a digitized or linear manner Digitized FM is best for signal tone modulation and provides very accurate center frequency at low deviation rates Linear FM is best for multi tone modulation and provides a ...

Страница 380: ... Takes into account limited tuning resolution available in linear FM Special Function 120 refer to How to access special functions on page 373 Model Number Option Band Minimum MHz Band Maximum MHz Mode 3 Mode 2 8665A 4120 4200 800000 20000000 8665A 3000 4119 99999999 400000 20000000 8665A 2060 2999 99999999 400000 10000000 8665A 1500 2059 99999999 200000 10000000 8665A 1030 1499 99999999 200000 50...

Страница 381: ... allows you to have the instrument synthesize the FM signal in a digitized or linear manner Digitized FM is best for signal tone modulation and provides very accurate center frequency at low deviation rates Linear FM is best for multi tone modulation and provides a more constant group delay than the Digitized FM The preset condition is FM Digitized Table 63 Operating characteristics for 8665A mode...

Страница 382: ...o the FM modulated signal to get better FM frequency response You may want to turn OFF the FM Delay Equalizer circuitry when the signal generator is used as the VCO in a phase locked loop application to reduce phase shift of when you want to extend the FM bandwidth to 200 kHz When OFF FM Indicator Accuracy is worse for rates of 1 5 kHz and better beyond 30 kHz Refer to the 8643A 8644B User s Guide...

Страница 383: ... into account limited tuning resolution available in linear FM Special Function 120 refer to How to access special functions on page 373 Model Number Option Band Minimum MHz Band Maximum MHz Mode 3 Mode 2 8665B 4120 6000 800000 20000000 8665B 3000 4119 99999999 400000 20000000 8665B 2060 2999 99999999 400000 10000000 8665B 1500 2059 99999999 200000 10000000 8665B 1030 1499 99999999 200000 5000000 ...

Страница 384: ...s the ON ENTER key to terminate data entries that do not require specific units kHz mV rad for example Example Special 1 2 0 ON Enter Table 65 Operating characteristics for 8665B modes 2 and 3 Characteristic Synthesis Mode Mode 2 Mode 3 RF Frequency Switching Time 200 ms 350 ms FM Deviation at 1 GHz 1 MHz 100 kHz Phase Noise 20 kHz offset at 1 GHz 130 dBc 136 dBc Figure 303 8665B Special functions...

Страница 385: ...e constant group delay than the Digitized FM 124 FM Dly equalizer This special function allows you to turn off FM delay equalizer circuitry When ON The preset condition 30 µsec of group delay is added to the FM modulated signal to get better FM frequency response You may want to turn OFF the FM Delay Equalizer circuitry when the signal generator is used as the VCO in a phase locked loop applicatio...

Страница 386: ...386 Agilent E5505A User s Guide 16 Reference Graphs and Tables ...

Страница 387: ...387 E5505A Phase Noise Measurement System User s Guide Agilent Technologies 17 System Specifications Specifications 388 Power Requirements 391 ...

Страница 388: ...temperatures up to 31 C decreasing linearly to 50 relative humidity at 40 C Air flow space required 102 mm 4 in on all sides System weight Benchtop 1 6 Meter Rack 2 Meter Rack Approximate typical 210 lbs 95 5 kg 431 lbs 195 5 kg 465 lbs 211 kg System dimensions Height Width with rack mounted flat panel display with benchtop PC and display Depth 711 to 915 mm 28 to 36 in 432 mm 17 in n a 1 016 mm 4...

Страница 389: ...close to the carrier If either of these conditions are not met system measurement accuracy may be reduced Phase detector input power 1 6 GHz carrier frequency R input 0 to 23 dBm L input 15 to 23 dBm Downconverter input range 1 GHz to 6 GHz 1 GHz to 18 GHz 1 5 GHz to 26 5 GHz External noise input port 0 01 Hz to 100 MHz Measurement accuracy 2 dB 1 0 MHz offsets 4 dB 100 MHz offsets Table 67 Operat...

Страница 390: ... an aborted measurement If the tuning range of the VCO source is too large noise on the control line may increase the effective noise of the VCO source Computer The minimum requirements for the E5505A phase noise measurement system CPU are Pentium microprocessor 2 4 GHz or higher recommended 1 GB of memory RAM 40 GB hard disk Microsoft Windows XP Pro Super Video Graphics Array SVGA GPIB Interface ...

Страница 391: ...aximum current drawn by an E5505A system that contains one of each type of instrument listed in the table The E5505A system is shipped with AC power cords appropriate for your location For information on an instrument s power line module see the instrument s separate user s guide Table 70 E5505A maximum AC power requirements Component 115 VAC 230 VAC System maximum one of each type of instrument b...

Страница 392: ...392 Agilent E5505A User s Guide 17 System Specifications ...

Страница 393: ...7 PC to test set connection standard model 398 PC to test set options 001 and 201 and downconverter connection 399 E5505A system connections with standard test set 401 E5505A system connections with test set option 001 402 E5505A system connections with test set option 201 403 This chapter contains information and diagrams for connecting the instruments in a racked or benchtop E5505A system ...

Страница 394: ...ardware connections without AC power applied Failure to do so may result in damage to the hardware GPIB connections are an exception they may be connected with power applied Make connections in a properly grounded environment Agilent recommends wearing grounding wrist or foot straps Failure to do so may result in damage to the hardware CAUTION Do not make a GPIB connection with an oscilloscope Doi...

Страница 395: ...5500A Standard N5500A Opt 001 N5500A Opt 201 N5501A N5502A N5507A N5508A N5508A Opt 002 0960 0053 Termination coaxial SMA male 50 Ω 4 3 3 1250 0207 Termination BNC 50 Ω 1 1 1 1250 0780 Adapter Type N male to BNC female 3 2 3 1 1250 0839 Termination coaxial SMC female 50 Ω 1 1 1 1250 1200 Adapter SMA male to BNC female 2 1250 1250 Adapter N male to SMA female 1 2 1 1250 2015 Adapter SMA female to B...

Страница 396: ...meter 1 Test set rear panel GPIB Downconverter rear panel GPIB 8120 3446 GPIB 10834B 2 meter 1 PC rear panel GPIB Test set rear panel GPIB E5505 80001 RF SMA male to BNC male yellow 1 PC digitizer card adapter IN Test set front panel ANALYZER 100 MHz OUT E5505 80002 RF SMA male to BNC male green 1 PC digitizer card adapter OUT Test set rear panel CHIRP SOURCE IN For Test Set Opt 001 E5501 20001 RF...

Страница 397: ...er to the back of the PC digitizer card as shown in Figure 304 2 Connect a GPIB extension to the GPIB connector on the PC to provide adequate clearance for the cable 3 Connect the following cables between the PC Digitizer card adapter and the test set see Figure 305 on page 398 and Figure 306 on page 399 SMA male to BNC male cable between the PC digitizer card adapter s IN connector and the test s...

Страница 398: ...0 50 kHz 1600 MHz INPUT SIGNAL POSSIBLE SIGNAL INPUT 100MHz 50 23dBm 50kHz 1600MHz MAXIMUM POWER 30dBm OUTPUT POWER POWER N5500A Test Set Standard test set Spectrum analyzer Digitizer input Digitizer output GPIB Display PC E5505a_test_set_con1 05 Apr 04 rev 1 50 Ω load termination OUT TUNE VOLTAGE GPIB IN CHIRP SOURCE TRACK GEN IN OUT MULTIPLEXER LABEL SERIAL NUMBER 154258 ICES NMB 001 ISM GRP 1 C...

Страница 399: ...ITH ATTENUATOR MAXIMUM POWER 30dBm OUTPUT POWER POWER N5500A Opt 001 Test Set OUTPUT RF ANALYZER 1 8 18GHz AUX LO IF 5 1500 MHz ANALYZER FROM TEST SET 10 VOLTS MAX CONTROL VOLTAGE 5 MHz 18GHz 5 15dBm SIGNAL INPUT RMT LSN TLK SRQ ERR ACT STATUS GPIB 5MHz 1GHz 10dBm 1GHz 18GHz 15dBm MAXIMUM POWER 0 VDC MAX SIGNAL INPUT POWER N5502A Downconverter Downconverter Test set all options Spectrum analyzer D...

Страница 400: ...truments before connecting the GPIB cable N5500A 01A 02A 07A 08A 5 You may connect other assets in addition to those supplied with the system either at this time or after running the confidence test 6 Lastly connect the power cord s to the AC power supply CAUTION Do not make a GPIB connection with an oscilloscope Doing so causes the E5505A system to malfunction and may result in damage NOTE For ea...

Страница 401: ...icense key PC Digitizer card Digitizer input To test set rear panel CHIRP source Digitizer output Optional frequency counter Oscilloscope recommended GPIB GPIB Indicates optional cable NOTE Display 23 dBm 50 kHz 1600MHz MAXIMUM POWER 20 mA MAX TUNE VOLTAGE OUT OF LOCK 100 kHz ANALYZER ANALYZER RF ANALYZER PHASE DET OUTPUT MONITOR 15dBm MIN 50 kHz 1600 MHz REF INPUT ERR ACT STATUS SRQ TLK LSN GPIB ...

Страница 402: ... ANALYZER ANALYZER RF ANALYZER PHASE DET OUTPUT MONITOR 15dBm MIN 50kHz 1600MHz 7dBm MIN 1 2 26 5GHz REF INPUT ERR ACT STATUS SRQ TLK LSN GPIB RMT NOISE 0 01Hz 100MHz 1V Pk 50 50kHz 26 5GHz INPUT SIGNAL POSSIBLE SIGNAL INPUT 0VDC MAX 100MHz 50 50kHz 1600 MHz 23dBm ATTEN 1 2GHz 26 5GHz 10dBm ATTEN 30dBm MAX WITH ATTENUATOR MAXIMUM POWER 30dBm OUTPUT POWER POWER N5500A Opt 001 Test Set OUTPUT RF ANA...

Страница 403: ...t set rear panel CHIRP source Digitizer output Optional frequency counter Oscilloscope recommended GPIB GPIB Indicates optional cable NOTE Display Test set Opt 201 Spectrum analyzer To PC digitizer To reference source optional To oscilloscope or counter monitor optional DC out tune voltage optional E5505a_opt201_conn_dia 14 Apr 04 rev 1 Downconverter Downconverter 50 Ω load Signal input to be down...

Страница 404: ...404 Agilent E5505A User s Guide 18 System Interconnections ...

Страница 405: ... 408 System Interconnections 415 PC Digitizer Software Phase 2 418 Agilent I O Libraries 419 Measurement Software Installation 424 Asset Configuration 426 License Key for the Phase Noise Test Set 439 This chapter contains information and procedures for installing or re installing the necessary phase noise hardware and software in an E5505A Phase Noise Measurement System PC ...

Страница 406: ...e software and hardware in the system PC involves the following tasks in the order listed 1 Install software for the PC digitizer card 2 Install the PC digitizer card PCB 3 Install the GPIB interface card PCB 4 Connect cables between the system PC and the phase noise test set 5 Install the Agilent I O libraries 6 Complete the I O devices configuration 7 Install the E5500 Phase Noise Measurement so...

Страница 407: ...zer software Step Action 1 Make sure your PC and display are on 2 Place the manufacturer s installation CD ROM in the CD ROM drive of the PC The installation wizard dialog box should automatically appear after a few seconds If it doesn t start it this way From the Start menu select My Computer and the CD ROM drive Find and select the file setup exe Click OK 3 Follow the instructions in the install...

Страница 408: ...the cover of the N5505A system Advantech PC a Remove the top two screws on the left and right sides of the PC WARNING Disconnect all power before removing the cover to your PC Failure to disconnect power could result in serious injury CAUTION Refer to your computer s documentation for installation safety instructions and specific instructions for opening your computer Be sure to perform these proc...

Страница 409: ... 409 b Carefully slide the cover away from the front of the unit then lift it off c Uninstall the internal hold down bar by removing the two screws that attach it and lift the bar out of the unit Figure 311 Slide cover off Figure 312 Remove hold down bar 1 2 ...

Страница 410: ... expansion slot between the cards for easier internal access 2 Remove their cover plates by unscrewing the securing screw and lifting them off the slot Save the blank cover plates for use if the cards are removed later Taking ESD precautions Figure 313 Vertically Mounted expansion slots Grounding wrist strap Expansion slot s CAUTION The PC Digitizer and GPIB interface cards are static sensitive de...

Страница 411: ...onnected from AC power Figure 314 shows a PC digitizer card 1 Insert the PC digitizer card edge connector into the PCI connector Gently rock the card into place do not force it Make sure the card is fully seated by pushing firmly on the edge of the card with the palm of your hand Figure 314 PC digitizer card Figure 315 Insert PC digitizer card ...

Страница 412: ... secure the card 3 Connect the digitizer adapter to the back of the PC digitizer card as shown in Figure 317 While you have access to the expansion slots also install the second piece of phase noise system hardware the GPIB interface card Figure 316 Secure card with screw Figure 317 Connect adapter to PC digitizer card ...

Страница 413: ... the PC disconnected from AC power Figure 318 shows a GPIB interface card 1 Insert the GPIB card in the PCI connector Gently rock the card into place do not force it Make sure the card is fully seated by pushing firmly on the edge of the card with the palm of your hand Figure 318 GPIB interface card Figure 319 Insert GPIB card ...

Страница 414: ...ver as described in the manufacturer s documentation For the system s Advantech PC re install the hold down bar with additional rubber bumpers if desired then replace the cover NOTE You may need a GPIB connector extender to provide adequate clearance between the GPIB cable and the computer chassis Figure 320 Secure card with screw Figure 321 Replace cover ...

Страница 415: ...00 MHz OUT Table 73 E5505A connectors and adapters Part Number Description N5500A Standard N5500A Opt 001 N5500A Opt 201 N5501A N5502A N5507A N5508A N5508A Opt 002 0960 0053 Termination coaxial SMA male 50 Ω 4 3 3 1250 0207 Termination BNC 50 Ω 1 1 1 1250 0780 Adapter Type N male to BNC female 3 2 3 1 1250 0839 Termination coaxial SMC female 50 Ω 1 1 1 1250 1200 Adapter SMA male to BNC female 2 12...

Страница 416: ...CK 100 kHz ANALYZER ANALYZER RF ANALYZER PHASE DET OUTPUT MONITOR 15dBm MIN 50kHz 1600 MHz REF INPUT ERR ACT STATUS SRQ TLK LSN GPIB RMT NOISE 0 01Hz 100 MHz 1 V Pk 50 50 kHz 1600 MHz INPUT SIGNAL POSSIBLE SIGNAL INPUT 100MHz 50 23dBm 50kHz 1600MHz MAXIMUM POWER 30dBm OUTPUT POWER POWER N5500A Test Set Standard test set Spectrum analyzer Digitizer input Digitizer output GPIB Display PC E5505a_test...

Страница 417: ...TH ATTENUATOR MAXIMUM POWER 30dBm OUTPUT POWER POWER N5500A Opt 001 Test Set OUTPUT RF ANALYZER 1 8 18GHz AUX LO IF 5 1500 MHz ANALYZER FROM TEST SET 10 VOLTS MAX CONTROL VOLTAGE 5 MHz 18GHz 5 15dBm SIGNAL INPUT RMT LSN TLK SRQ ERR ACT STATUS GPIB 5MHz 1GHz 10dBm 1GHz 18GHz 15dBm MAXIMUM POWER 0 VDC MAX SIGNAL INPUT POWER N5502A Downconverter Downconverter Test set all options Spectrum analyzer Di...

Страница 418: ...ou through a few last steps of installing the PC digitizer software Then proceed with installing the Agilent I O libraries To finish the PC digitizer software installation 1 Reconnect the power cord to the PC and the AC power supply 2 Power on the PC and the display 3 Follow the instructions in the installation wizard 4 Do not restart the PC at this time ...

Страница 419: ... must also re install the E5500 Phase Noise Measurement Software after the I O Library installation To install the Agilent I O libraries Step Notes 1 Make sure your PC and display are on 2 Place the E5500 Phase Noise Measurement System software CD ROM in the PC s CD ROM drive A window appears with the contents of the CD If the windowdoesn t appear navigate to the folder using the menu selections S...

Страница 420: ...4 Double click on wnm0101 exe 5 Select Full Installation and follow the instructions in the Setup exe wizard Accept the default settings To install the Agilent I O libraries continued Step Notes E5500_win0101_icon 05 Apr 04 rev 1 E5500_install_opt 22 Mar 04 rev 1 ...

Страница 421: ...un IO Config then click Finish 7 Click Auto Config Auto Config adds all configured PC interfaces to the right pane The right pane is blank until you initially run Auto Config To install the Agilent I O libraries continued Step Notes E5500_IO_lib_installed 04 Apr 04 rev 1 E5500_IO_lib_config 22 Mar 04 rev 1 ...

Страница 422: ... pane Then click on Edit When you press Edit the GPIB Card Configuration dialog appears 9 At the bottom of the GPIB Card Configuration dialog box press Edit VISA Config The Show Devices dialog box appears To install the Agilent I O libraries continued Step Notes E5500_IO_lib_autoconfig 05 Apr 04 rev 1 Edit E5500_edit_visa_config 04 Apr 04 rev 1 ...

Страница 423: ...elect Identify devices at run time 11 Click OK on each dialog box until you have exited the I O Config program 12 Restart your computer The next task is to install the E5500 Phase Noise Measurement software which is on the same CD ROM To install the Agilent I O libraries continued Step Notes e5500_install_show_dev rev2 10 9 03 ...

Страница 424: ...and the E5500 Phase Noise Measurement System software CD ROM is in the PC s CD ROM drive 2 Navigate to the CD ROM contents folder using the menu selections Start Run Browse and select the CD ROM drive You can also open and close the CD ROM drive to cause a window with the CD ROM contents folder to appear 3 Double click on Setup exe 4 Follow the instructions in the installation wizard Accept the de...

Страница 425: ...ftware places the E5500Phase Noise folder on the desktop as part of the installation process 6 Copy the E5500 User Interface UI shortcut and the E5500 Shutdown shortcut to the PC desktop This provides easy access to the E5500 software and the Shutdown utility 7 Restart the PC To install the E5500 software continued Step Note E5500_copy_icons 04 Apr 04 rev 1 ...

Страница 426: ...ing Up Asset Manager Before you use the Asset Manager to configure your system instruments you may need to take it out of Demo Mode Asset Manager runs in Demo Mode on initial installation or if it is installed on a PC to which no system instruments are attached You must invoke the Asset Manager to determine if it is in Demo Mode To set up Asset Manager Step Note 1 Navigate to the Asset Manager by ...

Страница 427: ...raphic with the word DEMO If it is not in Demo Mode the left pane shows a list of assets 3 Close the Asset Manager To set up Asset Manager continued Step Note E5500_asset_manager 23 Mar 04 rev 1 E5500_asset_mgr_demo_mode 04 Apr 04 rev 1 NOTE When Asset Manager is invoked from the E5500 main menu you must restart the E5500 software for any configurations changes to take effect ...

Страница 428: ...est set 1 Double click on the E5500 Phase Noise desktop shortcut This invokes the E5500 software and the main phase noise graph screen appears 2 From the menu select System Asset Manger This invokes the Auto Asset Wizard 3 Click on Asset Wizard on the Auto Asset Wizard dialog box 4 Select Test Set from the Asset Type drop down list and click Next In the Choose Asset Role box E5500_asset_wizard 23 ...

Страница 429: ...ace and Address box Table 74 on page 435shows the default device addresses 7 In the Address field type 20 the default address for the test set 8 In the Library field keep the default and click Next The Library field does not apply to this example It applies specifically to the GPIB interface card 9 Type Agilent N5500A or Agilent 70420A in the Asset Name field depending on your model In the Set Mod...

Страница 430: ...N550A test set is found on the rear panel On the 70420A it is found below the front panel This entry is optional 11 Type a comment in the Comment field if desired The comment associates itself with the asset you have just configured 12 Click Finish The Asset Manager window appears E5500_model_serial_num 23 Mar 04 rev 1 E5500_enter_comment 23 Mar 04 rev 1 ...

Страница 431: ...Test on page 39 The PC digitizer configuration procedure follows on page 432 Table 74 on page 435 contains the default GPIB addresses for the instruments in the system 13 View the test set information in the Asset Manager window and confirm that it is correct The left pane shows the list of asset roles and assets The right pane shows the asset information The right pane is information only The lef...

Страница 432: ...C Digitizer using Asset Manager Wizard from within the Asset Manager This is the most common way to add assets 1 From Asset Manager click Asset then click Add See Figure 324 2 From the Asset Type pull down list Figure 325 on page 433 select FFT Analyzer then select Next Figure 324 Add assets e5505a_user_add_asset_mgr ai rev2 10 20 03 ...

Страница 433: ...Guide 433 3 In the Choose Supporting ACM dialog click on II PCI20428W 1 then click the Next button See Figure 326 Figure 325 Choose asset type Figure 326 Select supporting ACM E5500_choose_asset_role 23 Mar 04 rev 1 E5500_choose_supp_acm 04 Apr 04 rev 1 ...

Страница 434: ...efault address for the II20428 PC Digitizer in the Address box Table 74 on page 435 shows the default device addresses c The Library pull down list does not apply to this example It applies specifically to either the Agilent GPIB or the National GPIB interface cards Figure 327 Choose the interface and address for the PC digitizer E5500_interface_address 23 Mar 04 rev 1 ...

Страница 435: ...esses Instrument GPIB Address Test set 20 Downconverter 28 Microwave downconverter 28 RF analyzer 17 FFT analyzer PC digitizer card 1 FFT analyzer 89410A 18 Source 1 19 Source 2 23 Counter 3 Agilent E1430 VXI digitizer1 1 The E5500 software supports this instrument although it is not part of the standard E5505A system 129 Agilent E1437 VXI digitizer1 192 Agilent E1420B VXI counter1 48 Agilent E144...

Страница 436: ...rnal See Figure 329 This designates the noise source on the PC Digitizer board as the noise source to be used for loopsuppression verification suppression verification 9 Click the Next button Figure 328 Choose model and serial number Figure 329 Select internal in baseband source E5500_NI_model_serial 23 Mar 04 rev 1 E5500_fft_analyzer_opt 23 Mar 04 rev 1 ...

Страница 437: ... comment associates itself with the asset you have just configured 11 Click the Finish button The Asset manager window appears See Figure 331 Figure 330 Enter a comment about the configured asset Figure 331 Asset manager screen showing configured PC Digitizer E5500_enter_comment 23 Mar 04 rev 1 E5500_NI_PCI_screen 23 Mar 04 rev 1 ...

Страница 438: ...e measurement system Configuring the Agilent E4411A B ESA L1500A Swept Analyzer 1 To configure the E4411A B Swept Analyzer follow the same steps you used to configure the test set Refer to Configuring the Phase Noise Test Set on page 428 2 In the Select Interface and Address box use 8 the default GPIB address for the E4411A B Table 74 on page 435 contains the default GPIB addresses for the system ...

Страница 439: ...mputer and display are on 2 Referring to Figure 332 navigate to the E5500 Asset Manager 3 Click Options and then click License Keys See Figure 333 on page 440 NOTE If you have ordered a preconfigured phase noise system from Agilent Technologies skip this step and proceed to Powering the System On on page 36 Figure 332 Navigate to E5500 asset manager E5500_asset_mgr_start_menu 04 Apr 04 rev 1 ...

Страница 440: ...box a Insert the E5500 License Key disk in the computer b Using Notepad load License_key txt See Figure 334 on page 441 Figure 333 Navigate to license keys E5500_license_keys 23 Mar 04 rev 1 NOTE The license key for your system is unique and may only be used with a specific N5500A test set serial number The license key may be found both on your license key document and in the file license_key txt ...

Страница 441: ...og box as shown in Figure 335 d Click the Set button The dialog box displays a message confirming licensing or indicating that there is a problem See Figure 336 and Figure 337 on page 442 Figure 334 License_key txt Figure 335 Copy keyword into license key field n5500a_install_license_key ai rev 2 10 17 03 E5500_licensing1 23 Mar 04 rev 1 ...

Страница 442: ... the PC Digitizer Performance Verification procedure in Chapter 20 to ensure that the digitizer and adapter are functioning properly Figure 336 Licensing confirmation Figure 337 Licensing error E5500_licensing2 23 Mar 04 rev 1 E5500_licensing_unable_verify 23 Mar 04 rev 1 ...

Страница 443: ...gitizer Performance Verification Verifying PC Digitizer Card Output Performance 444 PC Digitizer Card Input Performance Verification 449 This chapter contains information and procedures for verifying the performance of the NI DAQ PC digitizer card PCI 6111 and PC digitizer card adapter ...

Страница 444: ...ically to ensure the proper functioning of these two components which affect measurement accuracy Required equipment Multimeter or oscilloscope for reading output voltage To verify the PC digitizer card input s performance Step Notes 1 Turn off the phase noise software 2 Connect the PC digitizer card adapter s output to the input of either a multimeter or oscilloscope See connection diagram below ...

Страница 445: ...Q Measurement and Automation Explorer application Path Start Programs National Instruments Measurement Automation 4 Double click Devices and Interfaces in the Configuration content frame To verify the PC digitizer card input s performance continued Step Notes E5505a_ni_daq1 11 Jun 04 rev 1 ...

Страница 446: ...formance Verification 5 Double click on Traditional NI DAQ Devices then select PCI 6111 6 Click the Test Panels button To verify the PC digitizer card input s performance continued Step Notes e5505a_digop3a rev 1 24 jun 04 e5505a_digop3b rev 1 24 jun 04 ...

Страница 447: ...ion 20 Agilent E5505A User s Guide 447 7 Select the Analog Output Tab 8 Select DC Voltage output mode To verify the PC digitizer card input s performance continued Step Notes e5505a_digop4a rev 1 24 jun 04 e5505a_digop5a rev 1 24 jun 04 ...

Страница 448: ...cope reads 5 V 10 PC digitizer adapter output specification is 5 V 10 12 Enter 10 V in the DC Voltage window 13 Click the Update Channel button 14 Confirm that the multimeter or oscilloscope reads 5 V 10 PC digitizer adapter output specification is 5 V 10 To verify the PC digitizer card input s performance continued Step Notes e5505a_digop6a rev 1 24 jun 04 e5505a_digop6b rev 1 24 jun 04 ...

Страница 449: ...pter Perform this procedure periodically to ensure the proper functioning of these two components which affect measurement accuracy Required equipment Function generator Frequency 2 MHz Calibrated peak to peak To verify the PC digitizer card input s performance Step Action 1 Connect the PC digitizer adapter s input connector to the output of the function generator e5505a_digop_conn1 rev 1 24 jun 0...

Страница 450: ...Server Hardware Connections A green check mark appears on the button to confirm connectivity If a red circle with a slash appears check hardware connections and try again 4 Configure the function generator using the appropriate keys on the instrument Frequency 100 kHz Amplitude 100 mV peak to peak For instructions refer to the function generator s user s guide To verify the PC digitizer card input...

Страница 451: ...nction generator See diagram in step 1 on page 449 8 Click the Peak button The Frequency screen should reflect the 100 kHz power specification 29 00 dBv 0 25 dBv 9 Reconfigure the Function Generator Frequency 1 99 MHz Amplitude 100 mV peak to peak 10 Click the Peak button The Frequency screen should reflect the 1 99 MHz power specification 29 00 dBv 0 5 dBv 11 Close the FFT Analyzer s Asset Contro...

Страница 452: ...452 Agilent E5505A User s Guide 20 PC Digitizer Performance Verification ...

Страница 453: ...453 E5505A Phase Noise Measurement System User s Guide Agilent Technologies 21 Preventive Maintenance Using Inspecting and Cleaning RF Connectors 454 General Procedures and Techniques 458 ...

Страница 454: ...out using proper torque techniques this applies primarily when connectors in the system have been disconnected then reconnected RF Cable and Connector Care Connectors are the most critical link in a precision measurement system These devices are manufactured to extremely precise tolerances and must be used and maintained with care to protect the measurement accuracy and repeatability of your syste...

Страница 455: ... to the proper value Proper Connector Torque Provides more accurate measurements Keeps moisture out of the connectors Eliminates radio frequency interference RFI from affecting your measurements The torque required depends on the type of connector Refer to Table 75 Do not overtighten the connector Never exceed the recommended torque when attaching cables Connector Wear and Damage Look for metal pa...

Страница 456: ...ited States Environmental Protection Agency and contains tetrafluoroethane You can order this aerosol from Agilent see Table 76 2 Use alcohol and a lint free cloth to wipe connector surfaces Wet a small swab with a small quantity of alcohol and clean the connector with the swab 3 Allow the alcohol to evaporate off of the connector before making connections CAUTION Do not allow excessive alcohol to...

Страница 457: ...ould only be performed with the instruments mains power cord disconnected in a well ventilated area Connector cleaning should be accomplished with the minimum amount of alcohol Prior to connector reuse be sure that all alcohol used has dried and that the area is free of fumes WARNING If flammable cleaning materials are used the material should not be stored or left open in the area of the equipmen...

Страница 458: ...the various cable and connector types used in the system Read this section before attempting to remove or install an instrument Each connector type may have unique considerations Always use care when working with system cables and instruments Figure 338 GPIB 3 5 mm Type N power sensor and BNC connectors GPIB Type Connector ...

Страница 459: ...g the connector nut counter clockwise with a 5 16 inch wrench Always reconnect using an 8 inch lb torque wrench Agilent part number 8720 1765 Semirigid cables are metal tubes custom formed for this system from semirigid coax cable stock 3 5 mm Connectors with a gold hex nut The semirigid cables that go to the RF outputs of some devices have a gold connector nut These do not turn Instead the RF con...

Страница 460: ...oining them Turn the silver nut clockwise by hand until it is snug then tighten with an 8 inch lb torque wrench part number 8720 1765 Bent Semirigid Cables Semirigid cables are not intended to be bent outside of the factory An accidental bend that is slight or gradual may be straightened carefully by hand Semirigid cables that are crimped will affect system performance and must be replaced Do not ...

Страница 461: ... disconnect all cables on the front and on the rear panel Most cables are fairly easy to remove and reconnect and have no special considerations besides making sure you put the cables back in the right place Semirigid cables require more care especially when reconnecting them Make sure all semirigid cables on the front and back of an instrument are fully disconnected before removing the unit 3 Whe...

Страница 462: ...struments Note the location of cables for re installation 5 Remove the four corner screws on the front of the rack panel that secures the instruments in place The screws are located near the corners of the face of the instrument Use a 2 Phillips screwdriver 6 Slide both instruments as a single unit out from the front of the rack and set them on a secure flat surface 7 Detach the lock links that se...

Страница 463: ...ont links Rear links To remove an instrument from a benchtop system 1 Power off each instrument in the system For details see Powering the System Off on page 45 2 Unplug the selected instrument s power cord from the AC power supply 3 Remove the power cord and other cables from the front and rear of the instrument Note the location of cables for re installation ...

Страница 464: ...pecial considerations besides making sure you put the cables back in the right place Semirigid cables require more care especially when reconnecting them Make sure all semirigid cables on the front and back of an instrument are fully disconnected before removing the unit 3 To reconnect the semirigid cables carefully align them before you insert the male connector Do not insert the male pin in at a...

Страница 465: ...e rack mount ears The rack mount ears stop the instruments at the correct depth 5 Replace the rack panel in front of the instruments and secure the four corner screws The screws are located near the corners of the face of the instrument Use a 2 Phillips screwdriver 6 Confirm that the instrument is turned off 7 Connect the appropriate cables to the instruments front and rear including the power cor...

Страница 466: ...466 Agilent E5505A User s Guide 21 Preventive Maintenance ...

Страница 467: ...formation which you should review prior to working with your Agilent system The information contained in it applies to all Agilent supplied instruments in the system and the system as a whole It also contains information on servicing and obtaining support for an Agilent system or instrument including procedures for removing an instrument from a system returning it to Agilent and re installing it ...

Страница 468: ...ass 1 LEDs per IEC 60825 1 Equipment Installation Install the instrument or system so that the detachable power cord is readily identifiable and is easily reached by the operator The detachable power cord is the disconnecting device It disconnects the mains circuits from the mains supply before other parts of the instrument or system The instrument front panel switch is only a standby switch and i...

Страница 469: ...spectively It is designed to operate at a maximum relative humidity of 20 to 80 at 31 C or less non condensing This instrument or system is designed to operate at altitudes up to 2000 meters and at temperatures between 0 C and 40 C CAUTION Ventilation Requirements When installing the product in a cabinet the convection into and out of the product must not be restricted The ambient temperature outs...

Страница 470: ...uption of the protective conductor inside or outside of the products is likely to make the product dangerous Intentional interruption is prohibited IEC 348 clauses 17 3 3 c and 17 3 4 CAUTION Always use the three prong AC power cord supplied with this product Failure to ensure adequate earth grounding by not using this cord may cause product damage CAUTION The detachable power cord is the disconne...

Страница 471: ...mation about conditions and comply with international regulations Table 77 defines the symbols and markings you may find in a manual or on an instrument WARNING To prevent electrical shock disconnect the instrument and or system from mains before cleaning Use a dry cloth or one slightly dampened with water to clean the external case parts Do not attempt to clean internally Table 77 Safety symbols ...

Страница 472: ...ply circuit disconnecting it with the mains supply ON supply a switch with this symbol closes the instrument s power supply circuit connecting it with the mains supply Instrument markings Definition The CE mark is a registered trademark of the European Community The CSA mark is a registered trademark of the CSA International The C tick mark is a registered trademark of the Spectrum Management Agen...

Страница 473: ...is is to declare that this instrument or system is in conformance with the German Regulation on Noise Declaration for Machines Laermangabe nach der Maschinenlaermrerordnung 3 GSGV Deutschland Compliance with Canadian EMC requirements This ISM device complies with Canadian ICES 001 Cet appareil ISM est conforme a la norme NMB du Canada Table 78 German noise requirements summary Acoustic Noise Emiss...

Страница 474: ...equipment repair and service on the Web http www agilent com Click on the Test Measurement link then click on Select a Country Click on the Contact Us link for contact information WARNING There are no user serviceable parts inside the system Any servicing instructions are for use by qualified personnel only To avoid electrical shock do not perform any servicing unless you are qualified to do so WA...

Страница 475: ...Figure 340 The serial number has two parts The first part makes up the prefix and consists of four digits and a letter The second part makes up the suffix and consists of the last five digits on the label The serial number prefix is the same for all identical instruments it changes only if the electrical or physical functionality differs between instruments However the serial number suffix changes...

Страница 476: ...inal shipping container or a strong shipping container that is made of double walled corrugated cardboard with 159 kg 350 lb bursting strength The shipping container must be large and strong enough to accommodate your instrument and allow at least 3 to 4 inches on all sides for packing material 4 Seal the shipping container securely with strong nylon adhesive tape 5 Mark the shipping container FRA...

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