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NI PXIe-5624R Calibration Procedure

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© National Instruments

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7.

Call 

niIFDig ExternalCal v1 Host.lvclass:Amplitude Cal 

Initialize.vi

. Wire 

External 10 MHz Reference Clock

 to the 

reference clock 

source

 input.

8.

Call 

niIFDig ExternalCal v1 Host.lvclass:Amplitude Cal 

Configure.vi

.

9.

Configure the signal generator using the following settings:

Frequency: value of the 

frequency to generate (Hz) 

output from 

niIFDig 

External Cal v1 Host.lvclass:Amplitude Cal Configure.vi

Power level: value of the 

power to generate (dBm) 

output from 

niIFDig 

External Cal v1 Host.lvclass:Amplitude Cal Configure.vi

 plus 

12 dB

Reference Clock source: Internal

10. Configure the power sensor to correct for the 

frequency to generate (Hz) 

output from 

niIFDig External Cal v1 Host.lvclass:Amplitude Cal Configure.vi

 

using the power sensor frequency correction function.

11. Measure the power of the signal present at splitter output 1 of the power splitter using the 

power sensor. Record this value as the 

measured input power

.

12. Calculate the 

corrected input power

 using the following equation:

corrected input power 

measured input power + splitter balance

Tip

Find the 

splitter balance 

by choosing the correct data point from the 

Characterizing Power Splitter Balance

 section. Remember that certain frequencies 

are not measured due to harmonics aliasing back on the fundamental.

13. Call 

niIFDig ExternalCal v1 Host.lvclass Amplitude Cal Adjust.vi

Wire the 

corrected input power

 calculated in step 12 to the 

actual power (dBm)

 

input. 

Wire the 

frequency

 

output from 

niIFDig External Cal v1 Host.lvclass:

Amplitude Cal Configure.vi

 to the 

actual frequency (Hz)

 input.

14. Repeat steps 8 through 13 until the 

amplitude calibration complete

 output of 

niIFDig 

ExternalCal v1 Host.lvclass:Amplitude Cal Adjust.vi

 returns a value of 

TRUE.

15. Call 

niIFDig ExternalCal v1 Host.lvclass:Close External 

Calibration.vi

. Set the 

write calibration to hardware?

 input to TRUE to store the 

results to the NI 5624R flash memory.

Summary of Contents for NI PXIe-5624

Page 1: ...PXIe 5624...

Page 2: ...PGA converts data from the ADC into quadrature I Q data This DSP shifts the frequency of decimates equalizes and calibrates the data before storing it into DRAM Use Interactive Spectrum Acquisition Ho...

Page 3: ...oftware from ni com downloads Documentation You might find the following documentation helpful as you perform the calibration procedure NI PXIe 5624R Getting Started Guide NI IF Digitizers Help NI PXI...

Page 4: ...for this procedure Verifying absolute amplitude accuracy Adjusting internal frequency reference B22 option needed for this procedure Adjusting absolute amplitude accuracy Frequency range 4 MHz to 2 00...

Page 5: ...adapter Huber Suhner 31_3 SMA 50 1 1 _UE or Fairview Microwave SM4236 Test system characterization Frequency range DC to 2 GHz Impedance 50 Return loss 23 dB 3 5 mm m to 3 5 mm m adapter Huber Suhner...

Page 6: ...each verification procedure insert a delay between configuring all devices and acquiring the measurement Adjust this delay depending on the instruments used but make sure it is at least 5 000 ms for t...

Page 7: ...e verification and adjustment procedures use test points from 5 MHz to 2 005 GHz in 5 MHz steps for the splitter balance characterization Frequencies in which harmonics alias on the fundamental freque...

Page 8: ...rrection function 7 Use the power sensor to measure the power at the frequency from step 6 8 Repeat steps 5 through 7 by updating the signal generator frequency from 5 MHz to 2 005 GHz in 5 MHz steps...

Page 9: ...e signal generator frequency from 5 MHz to 2 005 GHz in 5 MHz steps Record the resulting measurements as splitter output 1 power Each frequency should have a corresponding value 16 Calculate the split...

Page 10: ...ate self calibration using one of the following methods Click Self Calibrate in the upper right corner of MAX Right click the name of the device in the MAX configuration tree and select Self Calibrate...

Page 11: ...ference using a signal generator Use digitizer mode of the NI 5624R Use Interactive IF Acquisition Without DSP Host vi in the Multirecord Acquisition sample project as a starting point 1 Connect the s...

Page 12: ...gle Tone Information vi 5 Calculate the deviation using the following equation 6 Compare the value determined in step 5 to the verification test limits in the following table where initial accuracy 20...

Page 13: ...e across 400 MHz of bandwidth for each center frequency is measured This procedure requires the test setup and data collected in the Characterizing Power Splitter Balance section Characterize the powe...

Page 14: ...front panel connector The following figure illustrates the complete hardware setup Figure 4 Absolute Amplitude Accuracy Verification Cabling Diagram 1 Power Sensor 2 SMA m to N f Adapter 3 Power Spli...

Page 15: ...sult as measured input power Note Power sensor readings are in dBm not watts 9 Calculate the corrected input power using the following equation corrected input power measured input power splitter bala...

Page 16: ...R flash memory Successfully complete all required verifications or successfully complete reverification following adjustment prior to updating the calibration date and time on the NI 5624R Complete th...

Page 17: ...panel connector to the NI 5624R IF IN front panel connector using an SMA m to SMA m cable The following figure illustrates the hardware setup Figure 5 Internal Frequency Reference Adjustment Cabling...

Page 18: ...he power splitter balance characterization data for the correct frequency as the following frequencies are excluded from the adjustment procedure due to harmonics aliasing back on to the fundamental a...

Page 19: ...that the NI 5624R and the signal generator share a common reference The following steps assume you have connected the signal generator reference frequency REF OUT to the NI 5624R REF IN connector 6 C...

Page 20: ...plitter output 1 of the power splitter using the power sensor Record this value as the measured input power 12 Calculate the corrected input power using the following equation corrected input power me...

Page 21: ...NI Refer to the Worldwide Support and Services section for information about support resources or service requests Worldwide Support and Services The National Instruments website is your complete reso...

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