Vaisala RVP900 User Manual Download Page 27

Page: 27 / 484

Figure 3 Calibration Plot for RVP901

Frequency measurement for AFC output (from burst sample)

See

7.2.3 Automatic Frequency Control (AFC) (page 176)

and

calculation over a wide dynamic range (WDR)

The RVP902 signal processing computer processes the

and

values to obtain the moment

data (for example,

, or polarization variables).

IF band pass filtering

See

3.1.3.2 Digital IF Band Pass Design Tool (page 27)

Phase measurement and correction of transmitted pulse for magnetron
systems (from burst sample)

The following table shows the RVP900 real-time signal corrections to the

samples from

the Rx.

Chapter 3 – Functional Description

Summary of Contents for RVP900

Page 1: ...M211322EN J User Guide RVP900 Digital Receiver and Signal Processor RVP900...

Page 2: ...pplicable at any given time and hereby disclaims any and all responsibilities related thereto This manual does not create any legally binding obligations for Vaisala towards customers or end users All...

Page 3: ...nsmit RF Example 35 3 2 RVP902 Signal Processing Computer 36 3 2 1 LAN Connection for Data Transfer or Parallel Processing 37 3 2 2 Open Hardware and Software Design 37 3 2 3 RVP902 Socket Interface 3...

Page 4: ...plink 80 5 TTY Non volatile Setups 87 5 1 Using the TTY Setup Menu 87 5 1 1 Factory Saved and Current Settings 88 5 1 2 V and Vz View Card and System Status 89 5 1 3 Vp View Processing and Threshold V...

Page 5: ...rization 181 7 2 7 Amplitude Correction for Tx Power Fluctuations 182 7 3 Time Series Signal Processing 183 7 3 1 Time Series and Doppler Power Spectrum Example 184 7 3 2 Frequency Domain Processing D...

Page 6: ...ata LSIMUL 289 8 12 Reset RESET 292 8 13 Define Trigger Generator Waveforms TRIGWF 293 8 14 Define Pulse Width Control and PRT Limits PWINFO 294 8 15 Set Pulse Width and PRF SETPWF 296 8 16 Load Anten...

Page 7: ...Command 347 A 10 Checking General Trigger Setup with Setup Mt Command 347 A 11 Initial Setup of Information for Each Pulse Width 349 A 12 Checking Burst Pulse and AFC with Setup Mb Command 350 A 13 C...

Page 8: ...uired Software for TS Recording 393 D 4 2 Configuring UDP Ports for TS Recording 393 D 4 3 Configuring Automatic Startup of tsimport and tsexport 394 D 4 4 Configuring Network Buffering for tsimport 3...

Page 9: ...ical Interfaces 439 G 6 1 RCP903 ASR9 WSP Interconnect Cabling 439 G 6 2 RVP901 WSP to ASR9 Radar 440 G 6 3 RCP903 ASR9 WSP Panel Interfaces 441 G 6 4 ASR9 WSP Panel Indicators and Switches 442 G 6 5...

Page 10: ...C Rejection 138 Figure 27 Example of a Filter With a Poorly Matched Filter 139 Figure 28 Example of a Poorly Matched Filter 148 Figure 29 Example of a Filter With Poor DC Rejection 150 Figure 30 Examp...

Page 11: ...4 Figure 66 TS Playback from a Separate Archive Host 405 Figure 67 Ascope Differences during RVP900 TS Playback 407 Figure 68 ASR9 WSP with RVP7 Architecture 432 Figure 69 ASR9 WSP with RVP900 Archite...

Page 12: ...nout for the MITEQ MFS xx xx xx xx 100K xxMP Synthesizers 79 Table 26 Bit Assignments for the IFDR Coax Uplink 82 Table 27 Digital AFC Pinmap Commands 84 Table 28 Settings Commands 88 Table 29 Analysi...

Page 13: ...332 Table 78 IF Waveform Generator 332 Table 79 RVP901 IFDR I O 332 Table 80 RVP901 IFDR Physical Specifications 333 Table 81 Digital Waveform Synthesis 333 Table 82 Physical and Environmental Charact...

Page 14: ...Table 127 RVP901 WSP Interface to ASR9 Radar 440 Table 128 RVP901 WSP SMA Connector Summary 440 Table 129 RCP903 ASR9 WSP Panel Connectors Defined for Customer s Systems Implementation 441 Table 130 A...

Page 15: ...IRIS and RDA Software Installation Guide M211318EN IRIS Programming Guide M211316EN IRIS and RDA Utilities Guide M211319EN IRIS Product and Display Guide M211317EN IRIS Radar User Guide M211452EN IRI...

Page 16: ...st CAUTION Note highlights important information on using the product Tip gives information for using the product more efficiently Lists tools needed to perform the task Indicates that you need to tak...

Page 17: ...o the RVP902 signal processor for further processing into moments The fully digital transmit functionality can produce outputs as simple as a COHO for a Klytsron system or as complex as a pulse compre...

Page 18: ...products in the EU market after July 1 2006 must pass RoHS compliance The maximum permitted concentrations are 0 1 or 1000 ppm except for cadmium which is limited to 0 01 or 100 ppm by weight of homog...

Page 19: ...RVP9IFD China RoHS Compliance RVP901 AC and RCP903 China RoHS Compliance Chapter 2 Product Overview 17...

Page 20: ...y wired in a NEMA electrical enclosure that is accessible only to a trained technician The ground earth connection should be attached directly to the IFDR case mounting screw and then brought to the p...

Page 21: ...e equipment chassis with a wrist strap and a resistive connection cord If you are unable to take either precaution touch a conductive part of the equipment chassis with your other hand before touching...

Page 22: ...RVP900 User Guide M211322EN J 20...

Page 23: ...ducts RVP901 IF Digital Receiver IFDR is a network attached FGPA based product that provides the receive and transmit functionality needed in a weather radar signal processor From the sampled IF input...

Page 24: ...s polarization switch controls and pulse width control Input The primary input to the RVP901 IFDR is the received IF signal The RVP901 IFDR has five 16 bit A D converters to sample the transmit pulse...

Page 25: ...cy agility to provide advanced signal processing The IFDR performs the initial processing of the IF digital data stream and outputs I and Q data values to the host computer through the CAT5e Ethernet...

Page 26: ...s and then compute a pair of 2880 point dot products on those data every 0 83 microseconds This can produce over sampled I Q time series with a range resolution of 125 m and a bandwidth as narrow as 3...

Page 27: ...ssing computer processes the I and Q values to obtain the moment data for example Z V W or polarization variables IF band pass filtering See 3 1 3 2 Digital IF Band Pass Design Tool page 27 Phase meas...

Page 28: ...valid range of the converter and it is possible to deduce information about the signal The configuration and test utilities can run either locally or remotely over the network Advantages Achieve a wid...

Page 29: ...nterference rejection algorithms See 7 2 5 Interference Filter page 178 The RVP901 IFDR places the WDR I and Q samples on the Ethernet line where they are sent to the computer s processor The I and Q...

Page 30: ...auto track feature This makes the automatic frequency control AFC robust to start up temperature changes and pulse width changes that can affect the magnetron frequency Quality assessments perform a 2...

Page 31: ...ly pre distorting the transmit waveform based on the measured transmit burst sample The IFDR has 2 SMA outputs for the IF Tx waveform The digital IF waveforms are generated by a 16 bit DAC with 65 dB...

Page 32: ...ability bandwidth to discern targets in range The solution is to increase the Tx bandwidth by modulating the overall pulse envelope to restore a reasonable range resolution The fidelity of the RVP900...

Page 33: ...ch a calibrated measurement of signal power can be obtained The log amplifier is required because it is almost impossible to build a linear amplifier with the required dynamic range Phase distortion w...

Page 34: ...ence between the magnetron frequency and the reference STALO frequency The AFC circuit is often troublesome to set and maintain Also since it operates continuously small phase errors are continually b...

Page 35: ...ut and more The signals are brought in through the connector panel RVP902 Signal Processor 19 rack mounted computer with a dual processor multi core running a Linux operating system 3 1 5 2 RVP900 Exa...

Page 36: ...l pol including for example Zdr PhiDP Kdp RhoHV LDR Which of these variables is available depends on whether the system is a single channel switching system alternate H and V a Simultaneous Transmit a...

Page 37: ...is better than a magnetron but the system is still constrained by limited linear dynamic range IAGC inaccuracy quad phase detector asymmetries phase shifter inaccuracies and so on RVP Digital Receiver...

Page 38: ...aveform generation requires an optional software license 3 2 RVP902 Signal Processing Computer The RVP902 signal processing computer hosts the Linux operating system and provides the computing resourc...

Page 39: ...parallel signal processors in real time 3 2 2 Open Hardware and Software Design RVP is an open architecture radar signal processor that uses Gigabit Ethernet to interface to the IFDR which samples th...

Page 40: ...g On initial socket connection request DspExport provides a response of either Nak indicating the connection failed and why or Ack followed by some connection information TheAck string is in the form...

Page 41: ...ompressed size This is true for RVP900 reads because the reader always specifies the read size Version Sends the IRIS version Read Data Available RDAV Example RDAV 100 2 means read up to 100 bytes of...

Page 42: ...from pulse to pulse along with the corresponding FIR coefficients that extract I Q from the Tx waveform Allows users to experiment with arbitrary waveforms for pulse compression and frequency agility...

Page 43: ...ssing for Weather Moment Extraction Using the R2 lag improves the estimation of signal to noise ratio and spectrum width Processors that do not use R2 cannot effectively measure the SNR and spectrum w...

Page 44: ...Doppler radar since this means for example that a 1 azimuth radial must be constructed from exactly 64 input I Q values RVP900 has the processing power such that when the sample size is not a power of...

Page 45: ...agnetron The digital frequency error is sent through the uplink to the IFDR in the receiver cabinet 3 3 2 Time Azimuth Averaging Autocorrelations are based on input I and Q values over a selectable nu...

Page 46: ...seous attenuation Uses calibration information supplied by host computer dBT Identical to dBZ but without ground clutter These standard parameters are output to the host application 3 3 6 Threshold Pr...

Page 47: ...e Unambiguous Velocity Intervals PRF1 PRF2 Unambiguo us Range km Unambiguous Velocity m s Unfolding 3 cm Wavelength 5 cm Wavelength 10 cm Wavelength 500 300 3 75 6 25 12 50 None 1000 150 7 50 12 50 25...

Page 48: ...e domain notch filter frequency domain fixed or variable width filters IIR filters of various selectable widths are available for either 40 dB or 50 dB stop band attenuation The filtered I Q values ar...

Page 49: ...es a time domain autocorrelation approach to calculate the parameters of the polarization co variance matrix that is ZDR LDR PhiDP RhoHV PhiDP Kdp and so on The standard moments T V Z and W are also c...

Page 50: ...ernal relays that control the transmitter pulse width The internal trigger generator drives 8 separate lines each can be programmed to produce a desired waveform The waveforms are stored in RAM and ca...

Page 51: ...leaves the board in a reset condition It verifies that the RDA software and setup configuration is present and uncorrupted Once validated the diagnostic image boots the RDA application The applicatio...

Page 52: ...supply up to 24 output control lines More Information Automatic Frequency Control AFC page 176 Installing DAFC page 74 Mb Burst Pulse and AFC page 93 RVP900 Product Architecture page 15 3 7 Expansion...

Page 53: ...or IRIS Analysis Functions as a radar product generator RPG to provide outputs such as CAPPI rain accumulations echo tops automatic warning and tracking and so on Optional software packages are provid...

Page 54: ...ally the controlling application is on the same computer but DspExport can also export to a remote host radar server computer on the network If this workstation runs IRIS software at least a 10BaseT c...

Page 55: ...tor panel The major modules supplied with RVP900 are RVP901 IF Digital Receiver IFDR which is typically mounted in the radar receiver cabinet RVP902 main chassis which is usually mounted in a 19 EIA r...

Page 56: ...aisala usually supplies turn key systems Some OEM customers purchase just RVP901 and integrate it themselves while customizing the processor and software 4 2 RVP901 IFDR Hardware Figure 17 RVP901 IFDR...

Page 57: ...components in a traditional analog receiver system AFC circuit AGC or IAGC circuit COHO on magnetron systems Band pass filters Line drivers for base band video LOG receiver QuadpPhase detector Removi...

Page 58: ...e RVP901 IFDR serves as a heat sink The hotter chips mounted on the printed circuit board are bonded to the heat sink Position the RVP901 IFDR so that a minimum of 20 cubic feet per minute of air can...

Page 59: ...veral Watts more than is required by RVP901 A ferrite choke around the supply wires near the terminal strip is also recommended For information on the power harness needed to supply power to the RVP90...

Page 60: ...tatus indicators A generic interconnect cable is available to breakout each of the 51 pin micro D connectors on the IFDR to a standard 25 pin and 37 pin female D connector A similar 62 pin cable is us...

Page 61: ...tl GND 2 12 14 32 4 23 TTLIO_PIN GND Comm ttl GND 3 13 15 33 5 24 TTLIO_PIN GND Comm ttl GND 4 14 16 34 6 25 TTLIO_PIN GND Comm ttl GND 5 15 17 35 7 26 TTLIO_PIN GND Comm ttl GND 6 16 36 37 8 27 TTLIO...

Page 62: ...ning protection Analog Inputs 6 analog differential inputs 10 V DC or low frequency signals Settle to within 0 1 of full scale value in 800 nanoseconds ADC conversion rate once every 0 5 sec Analog Ou...

Page 63: ...ND GND 32 33 34 35 37 39 41 45 49 4 2 5 RVP901 IFDR Status Indicators Two LEDs provide status information for the RVP901 IFDR and status of the communication links to RVP902 Table 18 RVP901 IFDR LED I...

Page 64: ...ain channel ADC D is the low gain channel IF burst pulse sample for magnetron IF COHO for Klystron Received over ADC E Optional reference clock Used for system synchronization in Klystron systems The...

Page 65: ...le to occasionally exceed the A D input saturation level at the strongest targets however inputs must not exceed 20 dBm RVP900 uses a statistical linearization algorithm to derive correct power levels...

Page 66: ...essing page 23 The procedure is identical to the manner in which phase is recovered in a magnetron system except that the COHO signal is used in place of a sample of the transmit burst There are two c...

Page 67: ...s with that external trigger and there is no synchronization jitter in the range bins The RVP901 IFDR can lock its sampling clock to an external system clock reference through the CLK IN SMA input Thi...

Page 68: ...on Null Frequency Bands in Synthesized Tx Output When RVP900 generates a synthesized Tx waveform the output frequency cannot be within the interval of frequencies 0 4 0 6 f where f is the sample cloc...

Page 69: ...digital filter having a bandwidth of 1 MHz then an input signal at 103 dBm has a signal to noise ratio of 0 dB A narrower FIR passband corresponding to a longer transmitted pulse decreases the quanti...

Page 70: ...measured when 25 or more pulses are used The overall dynamic range at 1 MHz bandwidth approximately 1 sec transmit pulse is 95 4 4 103 dB For a 0 5 sec pulse the dynamic range is reduced to 100 dB but...

Page 71: ...ange of the RVP901 IFDR so that the received echoes can be optimally processed When selecting the required gain we must make a trade off between preserving the receiver sensitivity that has been estab...

Page 72: ...the curve that limits the loss of sensitivity to 1 4 dB 0 65 dB The attendant loss of dynamic range falls between 5 5 dB 8 5 dB respectively Each axis of the plot has an important physical interpreta...

Page 73: ...cribed bandwidth and then dividing by the thermal noise power expected over that same bandwidth from an ideal amplifier having the same gain For example suppose that an amplifier with a gain of 20 dB...

Page 74: ...any particular relationship between the A D sample clock and the receiver s intermediate frequency You may operate at any IF that is at least 2 MHz away from any multiple of half sampling rate At 72...

Page 75: ...passband 4 3 Installing RVP902 Main Chassis RVP902 has two power supplies Disconnect power from both supplies when powering down or servicing unit WARNING 1 Mount the chassis in a nearby equipment rac...

Page 76: ...20 DAFC Module The following figure shows assembly diagram of the board 3 in x 3 75 in It can be installed in the radar system as a bare board or packaged in a small metal enclosure The RVP900 uplink...

Page 77: ...line to help protect the board against momentary application of non TTL voltages on its external pins However these resistors do impose a restriction on the input line configuration of the receiving...

Page 78: ...15 on Pins 1 16 Fault input on Pin 25 On Off AFC 16 format Bits 0 15 on Pins 25 10 Fault input on Pin 3 Off On AFC 16 format Bits 0 15 on Pins 18 19 6 7 21 22 23 11 10 9 20 8 12 25 13 24 Fault input...

Page 79: ...ting clock for the on board logic and there are two choices of frequency to use If jumper H2 is Off the crystal frequency should be equal to the IFD sampling clock faq and if H2 is On the frequency sh...

Page 80: ...n AFC frequency span of 5580 MHz 5600MHz This can be done with the following setups from the Mb section AFC span 100 100 maps into 3800 4000 AFC format 0 Bin 1 BCD 2 8B4D 0 ActLow NO AFC uplink protoc...

Page 81: ...MHz 8 22 24 100 MHz 2 23 12 10 MHz 4 24 25 100 MHz 1 25 13 10 MHz 2 26 Configure the DAFC pins Pins 1 and 14 are ground and are connected with wirewrap wire to the nearby ground posts Pins 2 and 15 a...

Page 82: ...n output from the IFDR Any hardware previously attached to the coax uplink can be driven from this IFDR port The uplink is a single digital transmission line that carries a hybrid serial protocol The...

Page 83: ...is a variable length burst window that is centered on the transmitted pulse and has a duration burst approximately 800 nanoseconds greater than the length of the current FIR matched filter The burst...

Page 84: ...he end of the burst window Subsequent data bits are sampled at uniform s intervals The data sampling rate can be in error by as much as one part in 75 while still maintaining accurate reception This i...

Page 85: ...trigger 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Pos Numerator 1 Denominator 1 PLL 16 The AFC 16 and PLL 16 formats cannot be interleaved for use at the same time since there would be no way to distingu...

Page 86: ...ed replacement to the original AFC 16 format If you only need 12 bits of linear AFC map the AFC range to the 2048 2047 numeric span and select binary coding format See 5 2 1 Mb Burst Pulse and AFC pag...

Page 87: ...bits switch in additional noise power when they are set with the upper bits making successively greater contributions Built in noise generator level IF input and burst input selection Data 6 5 Bits 6...

Page 88: ...RVP900 User Guide M211322EN J 86...

Page 89: ...and receiver waveforms are displayed in the time and frequency domain The digital FIR filter matches the characteristics of the transmitted pulse 1 To access the TTY menu a In the serial TTY or host c...

Page 90: ...See 5 1 2 V and Vz View Card and System Status page 89 Table 28 Settings Commands Command Description S Saves the current settings into the non volatile RAM R Restores those non volatile values so th...

Page 91: ...tly running Settings were last saved using V12 3 Then information about when the RVP900 was started current system time and implicitly the uptime RVP9 started at 13 07 33 3 JUN 2012 Current time is 13...

Page 92: ...ite MonApr216 01 14EDT2012 This line shows the status of optional GPS time synchronization of the RVP900 triggers and range bins GPS Inused AFC indicates the level and status of the AFC voltage at the...

Page 93: ...9 0x8888 LOG CSR DBT 0 75dB 18 0dB 5 0dB 0 149 0 449 0xFFFF AllPass VEL 0 75dB 18 0dB 5 0dB 0 398 0 449 0xC0C0 CSR SQI WID 0 75dB 18 0dB 5 0dB 0 398 0 449 0xA000 LOG SQI SIG ZDR 0 75dB 18 0dB 5 0dB 0...

Page 94: ...you browse the setup list Vaisala recommends making incremental changes to saved settings 1 Type R to restore the saved values 2 Type M to make the changes starting from that point The current value...

Page 95: ...Tx and Rx intermediate frequencies are usually the same you can choose them separately so that the RF up conversion chain for transmission can be different from the down conversion chain for reception...

Page 96: ...se YES The Minimum power for valid burst pulse parameter is the minimum mean power required in the burst pulse for it to be considered valid and suitable for input into the algorithms for frequency es...

Page 97: ...t be accurate to perhaps 10 KHz The accuracy for the question Design Analysis Window 0 Rect 1 Hamming 2 Blackman 1 cannot be achieved with only 1 pulse However several hundred unbiased individual esti...

Page 98: ...an only run between intervals of sustained data processing This is fine as long as the host computer allows a few seconds of idle time every few minutes If the RVP900 were constantly busy the AFC loop...

Page 99: ...s see burst frequency estimator Settling Time above AFC span 100 100 maps into 32768 32767 AFC format 0 Bin 1 BCD 2 8B4D 0 ActLow NO AFC uplink protocol 0 Off 1 Normal 2 PinMap 1 The AFC loop becomes...

Page 100: ...e or they may be retransmitted by the IFDR as a serial stream to be received by an outboard DAFC module which supports arbitrary remapping of its output pins Pinmap Uplink Protocol Parameters These pa...

Page 101: ...y range is always be the full 100 100 AFC span The number of sub intervals to check must be specified along with the STALO settling time after making each AFC change With the default values shown AFC...

Page 102: ...nal to the transmit power During calibration we record the burst pulse power If this number is available and provided to RVP900 at processing time then the processor can notice the difference and adju...

Page 103: ...outer tolerance during data processing 50 0 KHz AFC feedback slope 0 0100 D Units sec KHz AFC minimum slew rate 0 0000 D Units sec AFC maximum slew rate 0 5000 D Units sec The Motor Integrator loop qu...

Page 104: ...IF frequency at the present rate of change For example if we are 1 MHz away from the desired IF frequency and the measured rate of change of the IF burst frequency is 20 KHz sec then it is 50 seconds...

Page 105: ...on ID mismatch errors are listed in the RVP900 diagnostic log Limits 100000 5 000 000 bytes Receive buffer size for incoming UDP packets 1500000 This is the frequency of the acquisition sampling clock...

Page 106: ...unsigned integer tenths of degrees that is 0x0000 for 0 0x000a for 1 0x0e06 for 1 and so on If we apply a scale factor of 65536 3600 18 2044 to these units we get 16 bit binary angles in the standard...

Page 107: ...the filter type followed by however many parameters that type requires See 7 3 5 Clutter Filtering Approaches page 189 Spectral Clutter Filters Window 1 Default 0 Rectangular 1 Hamming Code 2 Blackma...

Page 108: ...e cases try selecting a variable Width 2 and Hunt 2 filter In general make your variable filters wider by increasing Hunt rather than by increasing Width This preserves more flexibility in how they ca...

Page 109: ...cope application the setting 0 User enables the Spect Win button At RVP900 start up 0 User refers to the settings saved in rvp9 conf block opprm filter bits 9 10 11 Default Spectral Window 0 User 1 Re...

Page 110: ...s differ from a strict time domain calculation in that an end around term is introduced as a result of circular rather than linear convolution Requesting PPP style autocorrelations correct this spurio...

Page 111: ...ably fast rate This behavior only occurs when running without angle syncing such as during IRIS manual and RHI scans To make these free running modes more useful you can establish a minimum hold off b...

Page 112: ...region at the top of the HiGain channel within which that separation remains steady and constant that is unaffected by eventually approaching the noise floor of the LoGain channel RVP900 continually m...

Page 113: ...Size and so on all apply to the high PRF portion of the BATCH trigger waveform The low PRF rate and sample size are derived from these high values using a slope and offset In the example the slopes a...

Page 114: ...fficients are used as weights Cubic Splines Smoothing and numerical derivatives calculation using a CSU s Adaptive estimation of specific differential phase algorithm KDP computation 0 LSQ 1 Weighted...

Page 115: ...bration reflectivity value Z0 when the current noise level changes from the level measured when the calibration was done See 7 4 3 1 Noise Correction to Reflectivity Calibration page 202 Enable noise...

Page 116: ...of user defined output triggers is limited to 12 including polarization output controls Number of user defined output triggers 6 Polarization Output Controls The next setting defines the number of po...

Page 117: ...r that is involved with the pre fire timing of the transmitter If you enable the burst pulse tracker you probably want to assign a YES to some of your triggers so that they remain fixed relative to th...

Page 118: ...econds and the active sense of each trigger generated by the internal trigger generator Set a width to 0 to inhibit the trigger on that line The Start time can include an additional term consisting of...

Page 119: ...0 are generally safe to use because they shift the trigger into the same pulse period that originally defined it For example a start time of 0 0 sec 0 98 PRT positions a trigger 98 of the way up to th...

Page 120: ...from a target at zero range appears at the radar receiver outputs This parameter adjusts the delay from the active edge of the external trigger to range zero This delay must be correct when RVP900 op...

Page 121: ...ency 30 0000 MHz Rx Intermediate Frequency 30 0000 MHz Filter Length RVP900 computes I and Q using a digital FIR matched filter Define the length of that filter in microseconds here FIR Filter impulse...

Page 122: ...ute which fits within the 8000 tap limit In dual polarization mode the 190 in the above formula is replaced with 95 Burst Frequency Estimator This estimator is mostly used with the Pb plotting command...

Page 123: ...lter is behaving as expected when presented with thermal noise The noise level s are shown in dBm and you may alter either one from the TTY The power up levels are assigned by default when the RVP900...

Page 124: ...VP900 is equipped with an IFDR that is configured for Tx waveform synthesis in the Mz menu See 5 2 7 Mz Transmissions and Modulations page 126 When digital Tx waveforms are synthesized the following q...

Page 125: ...luding whatever amplitude modulations may be included at the tails Waveforms are synthesized by the RVP900 using a 16 bit TxDAC followed by an analog bandpass filter centered at the midpoint of the IF...

Page 126: ...m optimization procedure for the Pa command See 6 8 2 Available Subcommands In Pa page 162 Each parameter has a minimum value a maximum value and a current value which can be changed from this menu Th...

Page 127: ...X to 0 95 results in a pulse having full amplitude over the middle 95 of its duration but then having raised cosine amplitude weighting applied to the leading and trailing 5 of its edges Table 33 Line...

Page 128: ...Bm Apply pulse to pulse phase modulation NO Fixed relative phase offset 0 000 Deg Transmit Waveforms Select the type of waveform to generate on the Tx B SMA output In the following example a pulsed tr...

Page 129: ...ital signal simulator Limits 100dB 0dB Noise level for simulated data 50 0 dB This question asks whether IF samples should be plotted with Nyquist flipping multiplication by 1 1 1 1 If YES the Pr and...

Page 130: ...st points 0 no output 1 RF Gate 2 RF Pulse Start 3 RF Drive 4 Filament Reset 5 Post Charge 6 Mod Charge 7 Mod Discharge 8 Trig Charge 9 Rx Prot Cmd 10 Rx Prot Rsp 11 Update In 12 Udate Time1 13 Ph Coh...

Page 131: ...creen and you can perform graphical checkup and alignment procedures remotely through a network RVP900 supports opcodes that allow the host computer to monitor the data being plotted 6 2 Plot Command...

Page 132: ...For example if the w subcommand widens something by a little bit the W widens it a lot This simple convention reduces the number of different subcommand keys that are needed and makes the interface e...

Page 133: ...f all triggers so that the burst pulse is properly sampled Refine the impulse response length if necessary so that all samples easily fit within the display window See 6 5 Pb Plot Burst Pulse Timing p...

Page 134: ...2 When you are satisfied that the plot is drawn correctly type Q or press ESC to return to the TTY monitor 6 5 Pb Plot Burst Pulse Timing For magnetron radars RVP900 relies on samples of the transmit...

Page 135: ...eighted center of mass COM of the burst pulse envelope This allows the processor to determine the location of the middle of the transmitted pulse within the burst analysis window The Pb plot displays...

Page 136: ...ample window The sample window is always drawn in the center of the overall time span Depending on the PlotSpan and location of the trigger edges triggers that do not vary within the plotted time span...

Page 137: ...nts or decrements the overall time span of the plot The available spans are 2 5 10 20 50 100 200 500 1000 2000 and 5000 microseconds The value is reported on the TTY as PlotSpan Z z Zooms the amplitud...

Page 138: ...ts the waveform s Signal Noise energy DC Indicates the nominal DC offset of the burst pulse A D converter This is of interest only as a check on the integrity of the front end analog components The va...

Page 139: ...lse signal strength is reasonably matched to the input span of the IFDR A D converter The maximum analog signal level is 8 dBm Exceeding this level produces distorted samples that would seriously degr...

Page 140: ...ing designed with the live waveform that it is intended to selectively pass The filter s frequency response is always drawn with its passband peak touching the top of the plot The vertical height of t...

Page 141: ...pear aliased at these 72 MHz multiples Two types of spectra can be plotted on the screen the frequency response of the FIR filter and the frequency content of the burst pulse itself The burst spectrum...

Page 142: ...es visible on most scopes Motion of the minor tick is apparent even with very small changes in burst pulse frequency a change of just 5 KHz can easily be seen This means that you can observe the frequ...

Page 143: ...z steps The value is reported on the TTY as BW Often a small change in passband width shifts the exact locations of the filter s zeros and may improve the DC rejection U u D d Implement the Manual Fre...

Page 144: ...r Range Resolution Ambiguity page 154 V v Increments or decrements the number of burst pulse spectra that are averaged together to create the plot The count ranges from one no averaging to 25 and is r...

Page 145: ...intermediate frequency as chosen in the Mb setup command DC Gain The filter s response to DC zero frequency input The value is a negative number in decibels or the word ZERO if the filter has a true z...

Page 146: ...ding AFC The U and D commands can be used to slew the voltage up and down If any of the following states appears it implies that AFC is enabled and that MFC is disabled NoBurst The energy in the burst...

Page 147: ...encies is 1 0 We can now examine what the filter loss dBloss would be if this pulse were applied to a band pass filter The filter loss is the ratio of the power that is passed by the filter divided by...

Page 148: ...als are performed over the Nyquist frequency band that is implied by the IFDR sampling rate Note that the two integrals involving have a constant value and need only be computed once They serve to nor...

Page 149: ...and 27 MHz 33 MHz respectively This is necessary to avoid picking up energy from the other receiver and interpreting it as out of band input power A consequence however is that the real out of band p...

Page 150: ...initial bandwidth equal to the reciprocal of the pulse width The main lobes of the two plots should more or less overlap Experiment with changing the FIR length and bandwidth to achieve a filter with...

Page 151: ...can optimize the FIR filter manually or automatically Manual Method Defining a nearly optimal filter requires a few minutes of hunting with the I W and N keys Each time you press any of these keys RVP...

Page 152: ...the matched filter This DC gain should be reduced even further if it is known that coherent leakage is present in the receive signal at a level greater than the 27 dBm worse case A D offset The follow...

Page 153: ...n through the AFC word making a transition approximately every 4 ms This helps test the wiring for digital AFC installations Type 0 9 or A O to enter a mode for directly controlling a static 25 bit di...

Page 154: ...to it clear load pwd_1 dat sz size tx_chained_waveform_0 length sz 1 time_scale 0 1 RVP_clock_MHz length 1 RVP_clock_MHz freq_scale 0 RVP_clock_MHz length RVP_clock_MHz RVP_clock_MHz length plot time_...

Page 155: ...rm_0 5850 5980 time_scale 5850 5980 imag tx_chained_waveform_0 5850 5980 xlabel Time in usec power_spectrum abs fft tx_chained_waveform_if plot freq_scale 5000 5700 power_spectrum 5000 5700 xlabel Fre...

Page 156: ...t_pulse_ambig long_pulse_ambig_sz size long_pulse_ambig short_pulse_ambig_length short_pulse_ambig_sz 1 long_pulse_ambig_length long_pulse_ambig_sz 1 long_pulse_ambig_time_scale 0 1 RVP_clock_MHz long...

Page 157: ...ppropriately scaled and that nearby targets can be seen clearly 6 7 1 Interpreting Receiver Waveform Plots The following figure shows an example of a plot from the Pr command The horizontal axis repre...

Page 158: ...line represents a 10 dB change in power The graph is scaled so that the LOG power reaches the top display line when the samples occupy the full amplitude span Using the previous figure as an example...

Page 159: ...xed onto the same fiber cable that carries the IF data samples Zero range is defined to occur at the center of the burst window the latter half of the burst pulse is visible when the plot begins at ra...

Page 160: ...and span of the IF sampling window and alter the format of the display The list of subcommands is printed on the TTY Available Subcommands within Pr L l R r Start range Left Right T t Plot time span U...

Page 161: ...he IF signal strength is not be quite this high Use larger zoom levels to see the weaker samples more clearly You may zoom in powers of two up to x128 Navg The number of spectra and or LOG powers that...

Page 162: ...ew opportunities for using low power solid state transmitters that employ very long pulse lengths 20 80 sec Transmitters of this kind are less expensive both to build and to maintain compared with tra...

Page 163: ...e vertical axis is interpreted differently in each case The instantaneous frequency across the full length of the pulse is shown in white The vertical scale is normalized to hold the overall frequency...

Page 164: ...given pulse length and bandwidth of the Tx waveform this command allows you to try thousands of combinations of FM shape and amplitude shape searching for the combination that minimizes the sum of PS...

Page 165: ...ters 0 9000 1 0000 0 1770 See 5 2 6 1 Tx Synthesis Options page 122 V v Shows how the overall compressed pulse Tx Rx system responds to the effects of target Doppler shift You can introduce frequency...

Page 166: ...and the plot updates each time a better waveform is discovered Follow the messages to check if the search is converging The process normally runs to completion on its own If the search takes too long...

Page 167: ...ow much information is discarded by the receiving filter in order to achieve the desired level of sidelobe suppression These two quantities often trade off against each other in receiver systems so th...

Page 168: ...Mt n Triggers for Pulsewidth n page 116 The following example shows a Pr plot of a 40 sec 5 MHz optimized waveform generated by the RVP900 Tx card and fed into the IFDR In the example the ideal Tx wa...

Page 169: ...pulse having a bandwidth of 2 MHz The energy in the pulse is sharply contained within and uniformly distributed over the 2 MHz frequency interval centered on the IF carrier This shows the ability of s...

Page 170: ...RVP900 User Guide M211322EN J 168...

Page 171: ...gnal processing techniques being used During operation the complex arithmetic is broken down into its real valued component parts in order to be computed by RVP900 For example the complex product s W...

Page 172: ...d Q time series or video sample from the nth pulse from a given range bin In cases where it is obvious the subscripts denoting the pulse time are dropped The descriptions of all the data processing al...

Page 173: ...Reflectivity factor Real T Uncorrected Reflectivity factor Real 7 1 2 IF Signal Conversion Process The following figure shows the overall process by which the RVP900 converts the IF signal into correc...

Page 174: ...e digital implementation of functions that are traditionally performed by discrete components in an analog receiver More Information RVP901 IFDR IF to I and Q Processing page 23 7 2 1 FIR Matched Filt...

Page 175: ...uted for pn For magnetron systems the N bn samples are centered on the transmitted burst For Klystron systems the N bn samples may be obtained from the burst pulse recommended or from the CW COHO If t...

Page 176: ...erve the full benefit of that investment by running 2 separate IF signals to the Primary HiGain and Secondary LoGain IFDR inputs A nominal channel separation of 25 dB 30 dB can be used to achieve an o...

Page 177: ...reduced which makes it difficult for the IFDR to make a smooth transition as it combines the data from both channels Too high a separation may also result in receiver components that are not practical...

Page 178: ...p whose purpose is to maintain a fixed intermediate frequency from the radar receiver The STALO is typically tuned 30 or 60 MHz away from the magnetron frequency The maximum tuning range of the AFC fe...

Page 179: ...for initializing the 2 fine tuning servos in radar systems that drift significantly with time and temperature When the radar transmitter is on but the burst pulse is missing it may be because it is e...

Page 180: ...that is anticipated and the error rates that can be tolerated For some environments it is possible that good results can be obtained with C1 C2 but RVP900 does not force that restriction Two variatio...

Page 181: ...esults for 16 dB Interference C1 C2 Alg 1 Missed False Alg 2 Missed False Alg 3 Missed False Alg 3 C1 2 dB Missed False 6 0dB 17 8 10 91 17 8 4 06 17 8 3 48 10 3 4 15 8 0dB 10 5 6 57 10 5 2 42 10 4 1...

Page 182: ...antly lower false alarm rate This is because of the somewhat improved statistics that result when the linear mean of Pn 2 and Pn 1 is used in the second comparison rather than just Pn 1 alone We recom...

Page 183: ...without too much worry about side effects 7 2 6 Large Signal Linearization When an IF signal saturates there is still considerable information in the signal since only the peaks are clipped The propri...

Page 184: ...itude correction is a unique feature of the RVP900 digital receiver Bench tests with a signal generator reveal that an amplitude modulated waveform having 2 0 dB of pulse to pulse variation is reduced...

Page 185: ...I and Q processing is done to obtain the meteorologically significant moment parameters reflectivity total power velocity width signal quality index clutter power correction and optional polarization...

Page 186: ...utter spectrum points are removed Time domain 5 pole IIR filtering with 40 and 50 dB rejection are also available in PPP mode but Vaisala recommends frequency based filtering Batch Mode A small batch...

Page 187: ...f denotes the Fourier transform of the continuous complex time series s t The Doppler power spectrum is real valued since it is the magnitude squared of the complex Fourier transform of s t In practic...

Page 188: ...ples which increases the variance or uncertainty of the moment estimates For example the variance of the total power is greater when computed from a spectrum with Blackman weighting compared to using...

Page 189: ...e and Blackman the widest Windows effectively reduce the number of samples resulting in higher variance moment estimates Rectangular is the best case Hamming is intermediate and Blackman provides the...

Page 190: ...he measured autocorrelation magnitude to the absolute received power However since many of the algorithms do not require absolute calibration of the power the gain terms are ignored in the discussion...

Page 191: ...xactly fill the scanning angle sector More Information Setup Operating Parameters SOPRM page 239 Load Antenna Synchronization Table LSYNC page 297 7 3 5 Clutter Filtering Approaches The following tabl...

Page 192: ...gh speed processors such as RVP900 offer sufficient storage and computational power to implement frequency domain filters that in some cases are adaptive Because of the superiority of these filters th...

Page 193: ...targets The result is that more accurate estimates of dBZ are obtained In extreme cases when the weather spectrum is very narrow there can still be some attenuation of weather of a broad filter is sel...

Page 194: ...The use of the edge points for interpolation is identical to the fixed width case This filter allows users to specify a narrower nominal filter than the fixed width case and then when the clutter is s...

Page 195: ...ground clutter a single weather target and noise Bi modal weather targets aircraft or birds mixed with weather would violate this assumption The width of the clutter is approximately known This is de...

Page 196: ...ittle clutter use of a rectangular weighting function leads to the lowest variance estimates of intensity mean velocity and spectrum width When there is a very large amount of clutter then the aggress...

Page 197: ...are first sorted in order of their power As shown in the figure the sorting places the weakest component on the left and the strongest component on the right The vertical axis is the power of the com...

Page 198: ...haracterize the clutter power The very substantial algorithmic work that has been done so far is to eliminate the proper number of central points The operator only has to specify a nominal clutter wid...

Page 199: ...sian weather model is used to repair the filter bias that is the damage that is caused by removing the clutter points An IIR filtering approach makes no attempt to repair filter bias rather the filter...

Page 200: ...which is positioned as indicated by the vertical line To the right the m value is the mean and the s value the standard deviation as averaged over all range bins 1000 in this example For velocity the...

Page 201: ...irplanes ships or other moving objects The first step in autocorrelation processing is the optional removal of point clutter There are 2 adjustable parameters for the point clutter algorithm TCM Point...

Page 202: ...se bins which have an estimated clutter to signal ratio that falls within the CCOR threshold interval By excluding isolated point clutter targets from the range average the sub clutter visibility of t...

Page 203: ...erly corrects for this For example if the receiver gain were to change by a factor k then we would measure a noise value of kN and an autocorrelation value of kTo that is 2 0 2 2 0 2 0 Thus the k s ca...

Page 204: ...ime is the same as the noise level at run time And that any changes in measured noise level were due to changes in receiver gain not sensitivity Modern digital receivers and low noise amplifiers are v...

Page 205: ...radar wavelength s is the sampling time 1 PRF 1 is constrained to be on the interval When 1 then V Vu where the unambiguous velocity is 4 If the absolute value of the true velocity of the scatterers i...

Page 206: ...1979 2ln 0 1 2ln where ln represents the natural logarithm This can be compared to the expression in the preceding section for SQI to illustrate that this expression for the variance is only valid wh...

Page 207: ...y For a zero width pure tone W 0 the SQI is a function of the SNR only for example for W 0 an SNR of 1 corresponds to SQI 0 5 The SQI threshold is typically set to a value of 0 4 0 5 In terms of the G...

Page 208: ...ise power independently The algorithm for CCOR is 10log 10log 1 1 The clutter power is computed from 0 0 The signal power S is then computed from 1 exp 2 2 2 W is the width that has been previously ca...

Page 209: ...ing RVP900 can accept or reject incoming real time data to remove range bins Rejected data may include that with Weak signal power Unreliable estimates of Doppler parameters Polarimetric parameters th...

Page 210: ...ction threshold is typically used to reject measurements when the clutter in a range bin is very strong i e when the calculated CCOR is a large negative number in dB The appropriate value depends on t...

Page 211: ...nsitive If you do not you should reduce your SQI threshold Note that if you average more pulses or ranges then the threshold level can usually be reduced CCOR This is used to eliminate clutter targets...

Page 212: ...ormly in all processing modes when dual pol or reflectivity data are specified as being thresholded by SQI This gives you more freedom in applying an SQI threshold to your LOG data because the cutoff...

Page 213: ...Bin Indicates Valid Bin Indicates Speckle X Figure 45 1D Speckle Filtering Algorithm Table 58 1D Speckle Filters Purpose Relevant Data Types Reflectivity data dBT dBZ ZDR LDR when using dual pol Dopp...

Page 214: ...peckle filter Table 59 2D 3x3 Speckle Filter Rules Center Point Action Assign Threshold Else Valid Center Point If there are none or only one other valid point in the 3x3 Do Nothing Pass the center po...

Page 215: ...artesian vectors then averaged and converted back to polar The 2D 3x3 speckle filter can be used with or without the 1D speckle filtering However the data is cleaner if both filters are applied The 2D...

Page 216: ...trip range bins At a constant PRF the second trip seam is always at the same range but in dual PRF random phase mode the seam is different each ray Thresholded bins at the seam of the high PRF can be...

Page 217: ...is the intercept of the straight line fit green with the noise level To understand why this geometric construction yields the value of Io Let GdB represent the overall gain of the RF and IF component...

Page 218: ...Verify with the radar manufacturer that no damage can occur to the signal generator if the transmitter is running during the calibration CAUTION 1 Raise the antenna up a few degrees to avoid ground th...

Page 219: ...99 km Span 50 usec 6 Set the signal generator to the approximate radar RF frequency with a power level corresponding to a strong signal 30 dB above the noise and use a CW signal not a pulse This signa...

Page 220: ...in the calibration Transmitter Pt r e v i e c e R r e l p u o C Sig Gen dBmsiggen IFDR Lt LFeed Coupler Feed Receive Path Transmit Path dBmFeed LCable LCoupler Pt Feed Figure 48 Overview of Losses th...

Page 221: ...utility See IRIS and RDA Utilities Guide 7 6 4 Determining dBZo The calibration reflectivity is determined from the radar equation as follows 0 10log 0 2 0 where Io is in mW corrected for receive loss...

Page 222: ...2 69 1016 5 2 500 1 1 19 953 2 2 0 6 76 106 6 3 2 1 Assume that I0 with loss correction is calculated to be 105 dBm 3 16 10 11 mW then dBZo is 0 10log 0 2 0 10log 6 76 106 1 2 3 16 1011 36 7 6 3 You c...

Page 223: ...tion of the long PRT interval is not specified directly by the host computer Rather the RVP900 Maximum number of Pulses Second setup parameter is used to compute how much delay to insert in order to i...

Page 224: ...respect However the DPRT 2 widths use an improved algorithm based on the two different PRTs and which avoids the SNR sensitivity of the DPRT 1 width estimator 7 8 Dual PRF Velocity Unfolding For a rad...

Page 225: ...which can be interpreted as a phase angle within the unfolded interval 4 Now if l and h are in a 3 2 ratio then 3 2 and thus 3 2 The angle represents a velocity phase angle in but with respect to an...

Page 226: ...the low PRF angle by dividing the plane into thirds centered on the difference angle The result angle is either 3 3 2 3 3 4 3 depending on which one falls into the acceptance Region 1 The resultant an...

Page 227: ...points come about because the original velocity intervals are mapped some integer number of times to create the unfolded interval Since each original interval has a clutter notch at DC it follows tha...

Page 228: ...longated in the radial direction On Klystron systems they have valid Doppler velocities On magnetron systems the Doppler velocities are not valid but the noise from the 2nd trip echoes can obscure val...

Page 229: ...each transmit pulse has a different phase The sequencing is controlled by RVP900 7 9 1 Random Phase Second Trip Processing Algorithm The following figure shows a schematic of the data processing for r...

Page 230: ...first and second trip echoes represent the echoes as they would appear individually The ideal 1st trip echo is the echo that would be measured if there were no second trip echo interference The ideal...

Page 231: ...echo the approach used in RVP900 is to filter the echo from the other trip the whitening filter This is shown in the figure The adaptive whitening filter removes both the clutter and the weather All...

Page 232: ...rmance depends on many factors primarily the spectral width of the dominant echo and the overall stability of the radar system The difficulties of removing a dominant other trip echo from a weather si...

Page 233: ...le PRF random phase For more information see 7 9 1 Random Phase Second Trip Processing Algorithm page 227 7 10 Signal Generator Algorithm Testing The IF signal generator tests that can be used to veri...

Page 234: ...maller than s that is it is fine for the range bin to be located in any higher order trip 7 10 2 Verifying PHIDP and KDP The PHIDP and KDP processing algorithms can be tested using CW signal sources a...

Page 235: ...ive to each other Adjusting the amplitude of either signal generator is not affect the p terms but it does have an interesting effect on SQI If T Z V W are computed from both channels combined then th...

Page 236: ...RVP900 User Guide M211322EN J 234...

Page 237: ...ormation Output Data page 47 8 1 1 Setting up Data Acquisition and Processing Although the internal RVP900 tables and parameters are set to reasonable values on power up you usually need to modify the...

Page 238: ...900 waits and does not proceed with its internal processing until space becomes available Despite the slowdown in performance you always obtain correct data no matter how long it takes to read it You...

Page 239: ...No Operation NOP NOP is useful when a number of words must be flushed through RVP900 without side effects This single word instruction is ignored by the signal processor 15 14 13 12 11 10 9 8 7 6 5 4...

Page 240: ...is elected Then parameters are computed at those 100 ranges and 100 bins of data are output 1 Pairs of samples are averaged If the averaging is to 1 samples are taken at the same ranges but pairs of b...

Page 241: ...followed by optional XARG parameters as needed 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 NTH 0 0 0 1 0 Command If Nth is 1 then no threshold values are set This means the system ignores input words 4 5 6...

Page 242: ...r words in the processed data that are output by the PROC command See also 8 23 Configure Ray Header Words CFGHDR page 308 ASZ The Any Spectrum Size bit requests that DFT processing algorithms clutter...

Page 243: ...ion of reflectivity data This bit also enables intervening gas attenuation correction HClass is 1D speckle filtered when Lsr or Dsr is set 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Log Slope65536 dB LSB I...

Page 244: ...ds THRESH page 315 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Weather Signal Power Threshold in 1 16 of dB Input 7 Weather signal power SIG is an estimate of the SNR of the weather component of the receive...

Page 245: ...01 DPRT 2 processing mode The trigger generator produces alternate short and long pulses and Doppler autocorrelations are computed using both pairs See 7 7 Dual PRT Processing Mode page 220 11XX Reser...

Page 246: ...nput words 4 5 6 and 7 Further quality tests such as the Polarimetric Meteo Index can be configured for each data type See 8 30 Set Individual Thresholds THRESH page 315 Each test either passes and pr...

Page 247: ...imagine four 16 bit quantities having the following names and values LOG AAAA CSR CCCC SQI F0F0 SIG FF00 The flag value needed to represent a given logical combination of threshold outcomes is obtain...

Page 248: ...e Input 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Intervening Gas Attenuation Correction dB km Input 17 Gas attenuation correction attempts to compensate for overall two way beam losses due to absorpti...

Page 249: ...hat is that Zdr is non zero even when observing purely spherical targets This calibration offset permits nulling out this effect The GDR offset accounts for the overall Tx Rx gain imbalance between th...

Page 250: ...Up to 7 bins may optionally be skipped on each side of the central bin prior to making these two comparisons Ena This bit is set to enable point clutter detection Flag bits are reported in the Flg ou...

Page 251: ...y even as the noise floor becomes elevated due to very strong clutter targets A value of 0 restores the RVP900 defaults from the Mf menu 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Melting Height in Meters...

Page 252: ...Refl Thresh Control Flag LOG and CSR 8888 Hex Velocity Thresh Control Flag SQI and CSR C0C0 Hex Width Thresh Control Flag SQI and CSR and SIG C000 Hex Zdr Refl Thresh Control Flag LOG AAAA Hex AZ EL...

Page 253: ...XARGS data words See 8 21 Pass Auxiliary Arguments to Opcodes XARGS page 306 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Copy of Data Word 1 Supplied by Host Controller Output 1 15 14 13 12 11 10 9 8 7 6 5...

Page 254: ...e range resolution at that pulse width The internal trigger generator is temporarily set to a special noise rate usually much lower than the operating rate during the process It is the user s responsi...

Page 255: ...inspected through the GPARM command as may the current range and rate values themselves When the range or rate are changed the user must make sure that the new trigger rate allows at least 32 km foll...

Page 256: ...14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0 0 MSB Log of Measured Noise Level LSB Input 3 The is the same number as GPARM output 6 See 8 8 Initiate Processing PROC page 255 and 8 10 Get Processor Parameters...

Page 257: ...rizontal Vertical Noise pulse 2 in 1 100 of a dB XARG 3 These fault bits are outputted in the latched status GPARM word 9 Ntg No Trigger during noise measurement Ttf Trigger too fast during noise meas...

Page 258: ...tput time with transmitter stabilization and data acquisition at the new rate Output data are selected by the upper 6 bits of the PROC command Packed archive output is selected by setting the ARC bit...

Page 259: ...mand word format for Synchronous Doppler Mode is 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ARC Z T V W ZDR Unfold KDP 0 1 0 0 1 1 0 Command The Command word format for Free Running Doppler Mode is 15 14 1...

Page 260: ...cts radial velocity data Mean velocity expressed as a fraction of the unambiguous velocity interval is computed from the unsigned byte N as sec 128 127 5 0 Indicates velocity data is not available at...

Page 261: ...e at this range 1 0 01 m s 65534 655 34 m s 65535 Reserved Code Z Selects clutter corrected reflectivity data The level in decibels is computed from the unsigned byte N as 64 2 The overall range is th...

Page 262: ...gned byte using a logarithmic scale The KDP angles are multiplied by the wavelength in cm to reduce dynamic range and then converted to a log scale separately for both signs The minimum value is 0 25...

Page 263: ...d Code RHV Selects dual polarization correlation coefficient RHV data The correlation coefficient is computed on the interval 0 0 1 0 using a square root weighting of the unsigned byte N as 1 253 0 In...

Page 264: ...from 45 0 dB in 0 2 dB steps as follows 0 Indicates no LDR data available at this range 1 45 0 dB 226 0 0 dB 254 5 6 dB 255 Reserved Code Same as 16 bit decibel format for Z RHO Selects Signal Qualit...

Page 265: ...lts from further methods of classification See sig_data_types h and HCLASS data description in IRIS Programming Guide SNR Signal to Noise ratio on the primary horizontal channel Uses the same storage...

Page 266: ...elect Time Series then a further choice may be needed to select the time series from the first or second pulse when using the Hybrid Pulse Compression scheme For the Random Phase major mode the possib...

Page 267: ...put voltage can be encoded properly A High SNR packed floating format is also available that offers nearly the same dynamic range but provides a 6 dB improvement in SNR that is a commensurate improvem...

Page 268: ...his would add 6 dB one more bit to the overall dynamic range and large signal SNR In the floating format we really only gain 3 dB half a bit because the RMS noises add independently on the positive an...

Page 269: ...ure that no clutter filters are being applied In pulse pair time series mode with dual receivers selecting H V produces data in one of two formats according to the Sum H V Time Series question in the...

Page 270: ...n the legacy version of LFILT the input words following the command specify the choice of filter to be applied at each of the selected range bins A fixed size filter table is always loaded regardless...

Page 271: ...d in and have overlapping sectors in which case the highest numbered slot that spans a ray s AZ EL midpoint is used Choosing the highest numbered encompassing slot is a subtle but important detail tha...

Page 272: ...ins of Filter Selections to Load 0 4200 XARG 2 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Lower AZ Binary angle XARG 3 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Upper AZ Binary angle XARG 4 15 14 13 12 11 10 9...

Page 273: ...utput Words Word Description 1 Revision Serial number 2 Number of Range Bins 3 Current trigger period 4 Current TAG00 TAG15 5 Current TAG16 TAG31 6 Log of Measured Noise Level 7 I Channel DC Offset 8...

Page 274: ...shold Flags 32 Log Slope 33 LOG Threshold 34 CCOR Threshold 35 SQI threshold 36 SIG Threshold for Width 37 Calibration Reflectivity 38 Reserved 39 Reserved 40 Range Averaging Choice 41 Reserved 42 Res...

Page 275: ...0 1 0 0 1 Command 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Rev Bits 3 0 Rev 6 4 Serial Number Output 1 Shows the revision and serial numbers of the RVP900 board This information is useful when computer s...

Page 276: ...ts 31 16 Output 5 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0 0 MSB Log of Measured Noise Level LSB Output 6 This value is scaled four times higher than the time series LOG format see 8 8 Initiate Process...

Page 277: ...ere positioned past the trigger range Bit 2 No trigger during PROC command Bit 3 PRT varied by more than 10 sec within portions of a processing interval that should have been at a fixed rate Bit 4 Err...

Page 278: ...rrent State of Affairs Output 10 Bit 0 No trigger or more than 50 ms since last trigger Bit 1 Error in loading trigger angle table See 8 16 Load Antenna Synchronization Table LSYNC page 297 Bit 2 PWIN...

Page 279: ...hout root privileges Bit 5 Problem creating daemon process Bit 6 Inconsistent setup values detected Bit 7 Ethernet MTU does not support requested frame size Bit 8 Processor is running in Test Debug mo...

Page 280: ...Properly Acquired Bins for Current Range Mask PRT Output 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 No of Valid Bins in Initial Part of Ray From Last PROC Cmd Output 17 15 14 13 12 11 10 9 8 7 6 5 4 3...

Page 281: ...the End TAG 0 bit in the output ray header as a blanking flag or as a normal TAG line Bit 13 Missing signal at IFDR 1 Burst Input Bit 14 Reserved zero Bit 15 Set when valid burst power is detected but...

Page 282: ...Width 2 Output 23 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Min Trig Period 0 16667usec Increments for Pulse Width 3 Output 24 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Four 4 bit Control Bit Patterns for Eac...

Page 283: ...ncrements Output 28 The desired trigger generator rate is that which was selected in the most recently issued SETPWF command or power up rate if SETPWF was not issued The current rate may be different...

Page 284: ...SOPRM page 239 Since the threshold levels for each data parameter can be different see 8 30 Set Individual Thresholds THRESH page 315 words 33 36 are taken from the velocity parameter 15 14 13 12 11...

Page 285: ...flectivity in 1 16 of dB Output 37 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Reserved Zero Output 38 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Reserved Zero Output 39 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Ran...

Page 286: ...2 16LSB 2 31 Output 44 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Noise Sum of I Squared MSB 1LSB 2 15 Output 45 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Noise Sum of Q Squared MSB 2 16LSB 2 31 Output 46 15 1...

Page 287: ...15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Vert Noise Stdev in dB 10 Horiz Noise Stdev in dB 10 Output 49 The noise standard deviations for each receive channel are normalized to the mean power The values...

Page 288: ...ence See 8 28 Configure Phase Modulation CFGPHZ page 313 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Interference Filter Parameter C1 in Hundredths of dB Output 53 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Inte...

Page 289: ...et the current trigger slew See 8 26 Set Trigger Timing Slew SETSLEW page 312 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Polarization Algorithm Choices Output 57 Bit 0 Use H transmissions for T Z V W Bit 1...

Page 290: ...PRT has been altered to preserve the desired trigger pattern Bit 4 Using High SNR packed I Q format Bit 5 Trigger sequence truncated due to insufficient pattern memory Bit 6 Time series data source i...

Page 291: ...utputting each ray The arrival of any other command during that time causes the simulated data mode to be exited and error bit 10 is set in the GPARM latched status word The error bit is also set if a...

Page 292: ...the acquisition and processing of live radar data 2 or 3 Load one pulse of data samples beginning with the following 4 word header and continuing with an array of items each representing a single ins...

Page 293: ...F16 12 Format Input 7 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Reserved Input 8 In format 3 each bin within the pulse is represented by two 16 bit floating point words having the exact same format as th...

Page 294: ...5 4 3 2 1 0 Nv Nse Fif Nv Nv 0 1 1 0 0 Command Nv Reloads configuration from the saved nonvolatile settings Nse Reset the receiver noise levels to the power up default value for all pulsewidths as def...

Page 295: ...for transmitter triggers scope triggers range strobes PLL gates and so on The writable waveform table is unique in that the detailed timing of trigger and related control signals can be easily adjust...

Page 296: ...pulse width code SETPWF defines selects which code is used The PWINFO command loads four codes at a time according to the UpperPW bits 00 loads codes 0 3 01 loads codes 4 7 and so on RVP900 drives fo...

Page 297: ...dentally selects one of the unused states If the internal trigger generator is not being used then the PRT limits no longer affect the trigger rate and transmitter protection becomes the responsibilit...

Page 298: ...as described under PWINFO The new radar PRT is passed in word 1 For all processing modes that use a fixed trigger rate this value defines the trigger period that is output at all times except during n...

Page 299: ...nchronization Table LSYNC RVP900 can operate in a mode where radar data are acquired in synchronization with the antenna motion along the azimuth or elevation axis This means that the user computer do...

Page 300: ...an vary by what is required to collect the SOPRM number of pulses If clear the angular width of each ray is fixed between successive table entries by adjusting the pulse count and reinterpreting the S...

Page 301: ...d the trigger angle table a Choose the number of table entries b Write the required number of words to RVP900 Supply the angles clockwise in a strictly increasing order They must neither reach nor pas...

Page 302: ...c The current ray then runs until the antenna passes outside of either limit at which point processing for that ray is terminated d Once this happens a new trigger angle is assigned based on which li...

Page 303: ...ing drawn All relevant status and data words are output once upon each receipt of this command Subsequently status and data is output only when a change has taken place 2 Disable the scope plotting ou...

Page 304: ...5 4 3 2 1 0 1 0 0 1 0 0 0 1 Int 7 Int 6 Int 5 Int 4 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 1 0 0 1 0 0 1 0 Int 11 Int 10 Int 9 Int 8 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 1 0 0 1 0 0 1 1 Int 15 Int 14...

Page 305: ...ver 5 decades of log range from 0 01km 1000km There are 50 table entries per decade of range The range in kilometers corresponding to an input word N is 10 N 1 devide 50 2 and the default correction t...

Page 306: ...RBACK permits some RVP900 internal tables to be read back for confirmation and diagnostic purposes This command is not generally used during normal data acquisition and processing 15 14 13 12 11 10 9...

Page 307: ...e mask spacing in cm for each pulse width 11 Current value of UIQ bits from Set Clr all prior operations 12 Individual threshold configuration for each data type This allows read back of the threshold...

Page 308: ...XARGS command is first executed with the additional argument count encoded in its upper 11 bits This is followed by the array of 0 2047 additional arguments At this point the XARGS command finishes an...

Page 309: ...and applied to each processed ray based on Range Azimuth and or Elevation The LFSPECS command allows this suite of filters to be redefined on the fly 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0 0 0 0 0 0...

Page 310: ...tic interpolation Similar to the variable width filter except that quadratic gap interpolation is used This filter is experimental and should not be used Type 3 SPFILT_GMAP Gaussian Model Adaptive Pro...

Page 311: ...ced with a flag indicating that the ray s PRF was low 0 or high 1 When trigger blanking is enabled bit zero of the end TAG word is replaced with a flag indicating that the trigger was blanked 0 or nor...

Page 312: ...ing of the ray Word 1 Low 16 bits of 32 bit clock counter Word 2 High 16 bits of 32 bit clock counter PBN Timeseries playback version number TID Task ID encoded as struct rvp900TaskID_IO 14 words tota...

Page 313: ...better statistics Vaisala recommends Alg 3 for general operational use The other algorithms are included mostly for historical reasons 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Threshold Parameter C1 in...

Page 314: ...nds that is ranging from 327 68 327 67 sec The permitted span is 20 sec This is the same format used in GPARM Output 56 which shows the present slew value 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0 0 0 0...

Page 315: ...e Phase Modulation CFGPHZ CFGPHZ configures RVP900 phase control output lines which determine the relative phase of each transmitted pulse In some cases the chosen phase sequence has side effects else...

Page 316: ...le angles that the phase modulation hardware can produce This is the recommended way to invoke SZ 8 64 coding You may also supply your own 32 pulse angle sequence 8 29 Set User IQ Bits UIQBITS UIQBITS...

Page 317: ...4 threshold numbers used by all data types and to select the threshold control flags for 5 of the data types See 8 4 Setup Operating Parameters SOPRM page 239 Use the THRESH command if you wish to app...

Page 318: ...1 0 Z T V W ZDR KDP Input 1 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Flg Phi Rho Ldr Phi Rho Ldr SQI RHV PDP Input 2 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 all spares Input 3 15 14 13 12 11 10 9 8 7 6 5 4...

Page 319: ...6 5 4 3 2 1 0 spare Input 10 8 31 Set Task Identification Information TASKID TASKID allows you to name the I Q data that are currently being acquired by RVP900 This naming information then becomes ass...

Page 320: ...led in with values best approximating those notions Auxiliary Number may be filled in with any value that you find meaningful 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0 0 0 1 0 1 1 1 1 1 1 1 Command 15 1...

Page 321: ...al sync angles This prevents the PRF seam from bobbling between two adjacent sync angles The SETPWF opcode deletes any alternate sectors that have been setup so far Thus you can only use the PRFSECT c...

Page 322: ...4 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Upper EL Binary angle Input 5 The following arguments specify a trigger period in the same manner as the optional form of the SETPWF command 15 14 13 12 11 10 9 8 7 6...

Page 323: ...n be used with both live and simulated I Q data See 8 11 Load Simulated Time Series Data LSIMUL page 289 In the simulated case you can overlay simulated physical targets on top of real physical target...

Page 324: ...15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Target Power Delta over Range Span in Tenths of dB signed Input 5 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Target Doppler Shift in Hertz signed Input 6 15 14 13 12...

Page 325: ...e amplitude correction to its I Q data The ACY and ACN bits force Yes and No responses If both bits are clear or both bits are set no change is made 8 35 Custom User Opcode USRINTR and USRCONT These o...

Page 326: ...om the configuration of the task and either the melting layer product parameters used in the latest melting product created or the melting layer product default parameters RVP900 can use spatially var...

Page 327: ...to feedback the melting layer information from IRIS to the RDA The melting layer altitude information is specified for each antenna angle and range This way the melting layer height can be used in di...

Page 328: ...bit integer XARG 7 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Melting layer thickness Unsigned 16 bit integer XARG 8 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Status Unsigned 16 bit integer XARG 9 The XARGS st...

Page 329: ...e of the corresponding angle in degrees 360 Bin starting Range of the first bin in centimeters Bin Spacing The product of the number of output bins by the step divided by the number of bins Melting la...

Page 330: ...15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 Melting layer altitude 1 Melting layer altitude 2 Input 3 Number of Mlbins 2 RVP900 User Guide M211322EN J 328...

Page 331: ...g 2 3 3 4 or 4 5 for 2X 3X or 4X de aliasing High sensitivity Zhv STAR Rhv STARmode processing 3 dB improvement detection gain IF digitizing 16 bits 100 MHz in 5 channels Number of range bins Up to 42...

Page 332: ...lds Signal to noise ratio SNR Used to reject bins having weak signals typically applied to dBZ Signal quality index SQI Used to reject bins having incoherent signals typically applied to mean velocity...

Page 333: ...B IF range 5 120 MHz Impulse response Up to 80 sec These very long filters are used with pulse compression Input Signals IF Received Signal 50 8 0 dBm full scale 20 dBm absolute max IF Burst or COHO 5...

Page 334: ...input 6 differential pairs 10V Signal must be low frequency with steps settling to 0 1 in 800 nanoseconds and a maximum sampling rate of 0 5 sec AFC output Digital AFC DAFC with up to 24 programmable...

Page 335: ...ity for placing the device If ordered without fans must provide a minimum of 20 cubic feet per minue of air flow across RVP901 enclosure fins Internal regulator An isolated supply with a 12 36V wide r...

Page 336: ...nthesis of analog waveforms that has simpler modulation requirements than are possible with TxDACs Can drive up to 13 dBm into 50 Outputs frequencies 5 MHz 105 MHz 9 6 RVP902 Signal Processing Compute...

Page 337: ...r supplies auto ranging 100 240V AC More Information RVP902 Signal Processing Computer page 36 Installing RVP902 Main Chassis page 73 9 7 RVP902 Safety Compliance Table 83 RVP902 Safety Compliance Ite...

Page 338: ...erver computer RVP903 Radar server computer and IO62 card Table 85 RVP902 IO Spare Parts Part Number Description 248384SP 1TB SSD 248386SP 512GB SSD 248382SP Redundant power 248392SP System fan 2 pcs...

Page 339: ...non condensing with a minimum of 20 cubic feet per minute of air flow RVP901 with AC Option 40 C 45 C 40 F 122 F 0 95 R H non condensing with a minimum of 20 cubic feet per minute of air flow RVP902...

Page 340: ...3 2 1 4 5 Figure 53 RVP902 IO Type Plate 1 Part name 2 Product code 3 Voltage current and frequency 4 Place of manufacture 5 Serial number in bar code RVP900 User Guide M211322EN J 338...

Page 341: ...this manual Do not write in this manual since it is replaced with an upgrade Make a copy Sign off on each test when it is complete If a test does not pass remedy the problem and repeat the test If the...

Page 342: ...11 Initial Setup of Information for Each Pulse Width page 349 A 12 Checking Burst Pulse and AFC with Setup Mb Command page 350 A 13 Checking Debug Options with the M Command page 351 A 14 Checking Tr...

Page 343: ...Digital Receiver is properly connected to AC DC line voltage according to supplied power converter RVP901 is mounted in the radar receiver cabinet or other convenient location RVP901 IF input connect...

Page 344: ...P901 Checklist Table 89 Power Up Checklist Task Checked OK Not OK Remarks When power is applied to RVP901 Red and green lights D7 may blink on boot and then green light is solid The red light is solid...

Page 345: ...y or on a remote computer with DspExportrunning Test Procedure Follow the steps in A 5 1 Checking Terminal Setup page 344 Checklist Table 90 Terminal Set Up Checklist Task Checked OK Not OK Remarks Pr...

Page 346: ...of available commands type help 4 To exit the menu and reload RVP900 with the changed set of current values type Q Settings are saved in non volatile RAM so they take immediate effect on start up You...

Page 347: ...Date For Vaisala Date A 7 Checking Board Configuration with Setup Mc Command Test Goal Verify that the TTY setups for the Board Configuration section are properly configured for the customer applicati...

Page 348: ...Verify that the TTY setups for the Processing Options section are properly configured for the customer application Test Equipment KVM connected Test Procedure 1 Enter the TTY setups through dspx 2 Iss...

Page 349: ...3 Set all the values as required for your operation Checklist Table 94 Clutter Filters Setup Checklist Task Checked OK Not OK Remarks Test procedure completed successfully Parameters set See 5 2 3 Mf...

Page 350: ...ces a trigger for the COHO latching and also for the transmitter pulse This circuit should be bypassed in an upgrade Purpose Start Time Pulse Width 0 ________ ________ ________ ____ sec ____ sec 1 ___...

Page 351: ...e PRF and the pulse width in seconds For example a PRF of 1000 Hz and 1 microsecond pulse width is a duty cycle of 0 001 Thus a transmitter with a 0 001 duty cycle limit could function at 1000 Hz and...

Page 352: ...ecklist Task Checked OK Not OK Remarks Parameters are set See 5 2 6 Mt n Triggers for Pulsewidth n page 116 Test Passed For Customer Date For Vaisala Date A 12 Checking Burst Pulse and AFC with Setup...

Page 353: ...Equipment KVM connected Test Procedure 1 Enter the TTY setups through dspx 2 Issue the Mb command once for each pulse width 3 Set all the values as required Checklist Table 97 Burst Pulse and AFC Set...

Page 354: ...Checklist Table 98 Debug Options Checklist Task Checked OK Not OK Remarks Test procedure completed successfully Parameters are set See 5 2 8 M Debug Options page 127 Parameters have been set Test Pas...

Page 355: ...A 15 Ascope Test Test Goal Verify that the Ascope utility functions properly Background The Ascope utility provides independent radar control and plotting for testing the radar and RVP900 Test Equipm...

Page 356: ...d Test Procedure 1 Use Ascope to select the desired pulse width at a saved PRF 2 Enter the TTY setups through dspx 3 Issue the Mb and turn off burst pulse tracking 4 Set the transmitter to radiate 5 I...

Page 357: ...detected an experienced technician must service the radar If the burst pulse power is too small or large check the status of the attenuators or amps in the burst pulse signal path You may need to adju...

Page 358: ...he filter width such that the DC Gain is either ZERO or less than 66 dB 6 Repeat for each pulse width that is used use the Mt command to change pulse width and record Pulse width FIRLength Bandwidth D...

Page 359: ...Command page 350 3 Use the setup terminal and display scope in the Pb plot burst mode to verify that the burst pulse is properly centered Any pulse width can be used 4 Set to MFC using the command an...

Page 360: ...mmand Plot burst spectrum and AFC 3 Type the command to enter the MFC manual frequency control mode Verify that the MFC mode is indicated by the Manual notation next to the AFC output indicator on the...

Page 361: ...the MFC mode to AFC a Type b Verify that the terminal indicator changes from Manual toAFC 7 Exit the Ps menu Checklist Table 104 MFC Setup Checklist Task Checked OK Not OK Remarks Test procedure compl...

Page 362: ...to see if the AFC properly tracks back to the correct frequency 4 Perform the tests listed above for each pulse width and verify that the AFC properly tracks the center frequency For pulse width 0 Fo...

Page 363: ...the cable connecting the IF signal into the IFD Record the powers again Total ______dBm Filtered ______dBm 7 Add attenuation and or amplification by an amount such that the Filtered noise power is app...

Page 364: ...ows the AFC to stabilize 2 Turn the radiate off but leave the receiver on since the test signal generator may be damaged by the transmitter 3 Elevate the antenna to 20 and point the azimuth away from...

Page 365: ...ng 13 Record RVP900 calibration values Checklist Table 107 Calibration and Dynamic Checklist Task Checked OK Not OK Remarks Test procedure completed successfully Parameters are set See 6 7 Pr Plot Rec...

Page 366: ...sec Use the T t command to set the plot span to 50 sec Use the V v command to set averaging to 1 sample 4 Set the signal generator power to a value that is approximately 60 dB above noise and observe...

Page 367: ...amplitude or phase artifacts Test Equipment Ascope utility See IRIS and RDA Utilities Guide Known clutter targets with no weather signal Test Procedure 1 Configure the radar for normal operation expe...

Page 368: ...ecklist Task Checked OK Not OK Remarks Test procedure completed successfully Test Passed For Customer Date For Vaisala Date A 25 Hardcopy and Backup of Final Setups Test Goal Make a hardcopy of all th...

Page 369: ...For Vaisala Date A 26 RVP901 TxDAC Stand alone Bench Test Test Goal Verify that the RVP901 TxDAC electrical I O is working properly in an isolated environment Test Equipment IRIS dspx utility IF sign...

Page 370: ...should be connected directly to the IFDR SMA input connector not through any bandpass filter 8 Verify the plot shows a single strong spectral line at the selected Intermediate Frequency and that any s...

Page 371: ...Appendix B RVP901 IFDR Technical Drawings Figure 55 RVP901 IFDR Top and Front Face Appendix B RVP901 IFDR Technical Drawings 369...

Page 372: ...Figure 56 RVP901 IFDR Right and Left Sides Figure 57 RVP901 IFDR Fan Side Heat Sink More Information RVP901 IF Digital Receiver page 21 RVP900 User Guide M211322EN J 370...

Page 373: ...example gcc gdb make More Information Public API page 40 C 2 RVP Code Organization RVP internal APIs provide abstraction from the underlying hardware This means developers do not need to worry about...

Page 374: ...em triggers and timing and install transmit waveforms and receiver FIR filter coefficients The Timeseries API is implemented in these threads as is the opcode command interpreter See 8 1 Host Computer...

Page 375: ...developer model the open code is the delivered code It is not example code nor an abridged form of the final delivered algorithms Table 113 Software Maintenance Model Developer Tree Portion Descriptio...

Page 376: ...w tree For more information see IRIS and RDA Software Installation Guide After an upgrade you must build ind install your customized version of RVP and RCP C 3 Debugging and Profiling Your Code While...

Page 377: ...y SNOISE The GPARM opcode is received and the 64 output words that it produces are displayed Watching the opcode level activity of the signal processor is helpful when debugging both custom driver cod...

Page 378: ...P 77 Frags 8150 8150 120 Bins 4086 0 PRT 324000 324000 iMisc 733d7451 Az 130 34 El 154 59 UDP 87 Frags 8150 8150 120 Bins 4086 0 PRT 324000 324000 iMisc 548062a8 Az 143 92 El 138 08 UDP 97 Frags 8150...

Page 379: ...t seems to be falling behind and tries to gracefully skip pulses in order to catch up Custom CPI algorithms for intensive major modes should be written with the same sort of feedback For more informat...

Page 380: ...in the first place On the second invocation the demo callback requests a delay of 2500 on the 1 MHz timer 2 5 ms and a delay of 5 counts on the trigger timer The RVP trigger is selected as the clock s...

Page 381: ...ed it is possible that ddd cannot find all its symbols b Type cd home operator src rda rvp9 main make j2 cd open ddd rvp9main The SITE and OPEN code is first compiled in the private development tree a...

Page 382: ...erably with procs 0 3 In another terminal window a To builds the new RVP9 Proc code and start the debugger type cd home operator src rda rvp9proc make j2 cd open ddd rvp9proc b To start the subprocess...

Page 383: ...s statistics in the gmon out file that is produced when the running program exits 1 The RDA Makefiles are setup to build profiled versions of either RVP9 Main or RVP9 Proc executables Define one of th...

Page 384: ...copy the prototype code to separately named files in the rvp9main site and rvp9proc site areas and then make the desired changes There are 4 major mode slots reserved for custom user applications 2 De...

Page 385: ...getAzElPosBtime sampleLiveAzElPos_f sampleLiveAzElPos insertLiveAzElPos_f insertLiveAzElPos frontPanelDisplay_f frontPanelDisplay This structure allows new objects to inherit existing properties of ol...

Page 386: ...ad runs at a priority that is higher than any other RVP thread This allows it to preempt other activities to achieve near real time behavior but it should always be coded as efficiently as possible an...

Page 387: ...ead and is made possible by having this hardware support at the IFDR level C 5 2 Standard Trigger and Antenna Event Example See the rvp9main open rtctrl c file for the standard RVP code for live trigg...

Page 388: ...ta SIMD instructions that comprise the core of the MMX technology and Streaming SIMD Extensions These technologies can improve the performance of computation intensive signal processing applications T...

Page 389: ...n executable form The license does not allow any additional programmers to develop their own code as an extension of Vaisala s license The IPP license is a per developer license There are no restricti...

Page 390: ...RVP900 User Guide M211322EN J 388...

Page 391: ...e Tsarchive Records time series to a local disk This can be on RVP or a separate networked archive host Supports both archive and playback licensed separately Ascope utility Can be used in playback mo...

Page 392: ...series data reside in memory The time series can be written to the TS API from one of the following sources From a local RVP900 From a local disk archive From a remote network host with tsimport tssw...

Page 393: ...roc n extracts TS from the TS API and processes the data to obtain the moments To view these processes use the v command in dspx A remote archive host is most likely not from RVP900 In this case these...

Page 394: ...C ts exec tsclientshell C ts archive tsarchAS C D 3 3 Extracting Pulses with Sequence Numbers Because there is a ring buffer filled with time series a reader should first get the most recent pulse an...

Page 395: ...igured D 4 1 Required Software for TS Recording The TS archive software is part of the Vaisala s RDA release which is installed by default on all RVP900s and RCP8s but it is not installed on IRIS syst...

Page 396: ...t all recipients can handle the traffic and that there are no 10baseT network sections D 4 3 Configuring Automatic Startup of tsimport and tsexport 1 Login as root 2 Use the chkconfig command to add t...

Page 397: ...elp Print this list port port Specify the port number to use All other options ignored tsexport help tsexport command line options broadcast broadcast address daemon Run as daemon debug Print diagnost...

Page 398: ...VP or a custom user application for processing Table 119 TS Switch Status Indicators Color Description Green Source successfully selected Yellow Source is available but not currently selected Red Sour...

Page 399: ...Figure 61 TS Archive Utility 1 Log in as operator 2 Start the TS Archive utility by typing tsarchive Appendix D Time Series Recording 397...

Page 400: ...cted archive directory partition For example if the selected archive directory is bigdisk tsarchive the Partition field shows the used total disk space for bigdisk The values displayed include all fil...

Page 401: ...in these two fields to narrow the list of products by time of day Day Month Year Enter or select a day month or year to narrow the list of products by date Show Files Control how many files to includ...

Page 402: ...etes the files This is helpful when you select a large list of files for deletion Remove Tags Clears the D or P tags Popup tsview Provides file information in another window D 7 Software Application E...

Page 403: ...process to the TS API RVP9Proc n extracts time series data and processes it The configuration information is obtained from and data are passed to user applications through the DSP Lib functions The ts...

Page 404: ...as shown in D 7 1 RVP900 in Normal Real Time Operation page 401 Utility Settings TS Switch Local RVP900 TS Archive Record This configuration records to a local disk on RVP900 Recording to a dedicated...

Page 405: ...hosts on the network Figure 64 TS Record on Separate Archive Host In this case the TS Switch is set to write IQ data from the tsimport network source Typically this is a 100 or 1000 Base T LAN connect...

Page 406: ...on case shown in D 7 1 RVP900 in Normal Real Time Operation page 401 except that the archive is the source rather than the real time operation The difference is that applications that use the time ser...

Page 407: ...ve to the TS API tsexport sends these through a UDP broadcast over the network to an RVP900 for processing The diagram for the corresponding RVP900 would be identical to the one shown in this example...

Page 408: ...1 Select the directory that contains the TS data to be played 2 Under TS Source select Local Archive 3 Make sure the light is green 4 Select the files that you wish to playback right click and select...

Page 409: ...ar and for these the archived value is displayed You cannot alter the fields There are other parameter fields that can be changed just like when you use Ascope with real time data such as the paramete...

Page 410: ...lay appropriately You are free to select the data processing and display parameters on the fly as playback is continuing and repeating When Ascope is set the way that you want it you can use the TS Ar...

Page 411: ...bar to bring up the Task Scheduler menu Make sure it says Passive on the top menu bar 8 Select the task that matches the data 9 Select Go Schedule for that task It toggles to running Wait for data to...

Page 412: ...ions For example tsview help To see the options see D 10 3 Tsview Command Line Options page 411 D 10 2 Starting tsview Sample Session In this session you view the pulse header information for the 101s...

Page 413: ...having to specify the full path and to allow the X window center button and copy paste technique to be used to avoid typing file names In the archive directory use the ls command to view the files tha...

Page 414: ...the case where ascope is used for RVP900 operation there is no concept of a sweep and the sweep number is set to 0 For RHI scanning the concept of a sweep is the same except that it is an elevation s...

Page 415: ...on See D 10 2 Starting tsview Sample Session page 410 D 11 TS Record Data Format Each TS file recorded to disk contains a run of 1 or more pulses which are from the same basic RVP900 configuration In...

Page 416: ...ngle format Power 6dBm 10 x log10 I2 Q2 Angle atan2 Q I The first time series sample number is from the burst pulse This is followed by a sample from each range bin with data The iNumVecs field in the...

Page 417: ...samples for the 2 channels fNoiseStdvDB 0 00540576 0 00540576 Standard deviation of the noise samples fNoiseRangeKM 525 Range at which the last noise was taken fNoisePRFHz 250 PRF at which the last n...

Page 418: ...PolarBits 0 Polarization control bits iTxPhase 182 Transmit phase 1 deg 16 bit binary angle iAz 16381 Azimuth 89 98 deg 16 bit binary angle iEl 179 Elevation 0 98 deg 16 bit binary angle iNumVecs 401...

Page 419: ...1 SYNC Byte C0 Hex 2 Identification byte User Choice 3 Diagnostic Results 0 6 D6 GP11 D6 Error loading config setup files D5 GP11 D5 IO62 card 2 failure D4 GP11 D4 IO62 card 1 failure D3 GP11 D3 Tx ca...

Page 420: ...GP10 D1 Error loading trigger angle table D0 GP10 D0 No trigger 9 Immediate Status 8 14 D6 GP10 D13 compute processes 1 bit 1 D5 GP10 D12 compute processes 1 bit 0 D4 GP10 D11 Current unfolding mode...

Page 421: ...fined Major mode 1 supported D4 GP55 D7 Problem with digital transmitter clock D3 GP55 D6 Could not generate the requested phases D2 GP55 D5 DSP supports DPRT 2 algorithms D1 GP55 D4 Last burst pulse...

Page 422: ...ing last PROC command D4 GP9 D4 spare D3 GP9 D3 PRT varied by more than 10 microseconds D2 GP9 D2 No trigger during PROC command D1 GP9 D1 Trigger too fast during noise measurement D0 GP9 D0 No trigge...

Page 423: ...size D2 GP31 D9 Output is in 16 bit format D1 GP31 D8 Enable clutter microsupression D0 GP31 D7 Use 3 lag processing for widths 23 SOPRMS Status 14 21 D6 spare D5 spare D4 spare D3 spare D2 spare D1 G...

Page 424: ...st Char Function 1 SYNC Byte AF Hex 2 Identification byte User Choice 3 4 Burst pulse frequency IFDR 1 5 6 Burst pulse frequency IFDR 2 7 8 Burst pulse power IFDR 1 9 10 Burst pulse power IFDR 2 11 12...

Page 425: ...ctory so that you can always return to the factory defaults 1 Login as radarop 2 Type cd usr sigmet config 3 Launch one of the text editors provided in the system gedit softplane conf A user friendly...

Page 426: ...that are used to define the logical interface to the softplane These are divided into status inputs also called indicators and control outputs also called requests For example sPedAZ0 corresponds to t...

Page 427: ...16 bits of antenna azimuth angle relative to the earth moving platform cEarthEL 15 0 16 bits of antenna elevation angle relative to the earth moving platform cServoPwr To control servo power on cCabin...

Page 428: ...king is requested usually from an external source sRadiate Radiate on indicator sAirflowFlt Cooling airflow fault indicator sWavegpFlt Wave guide pressure fault indicator sInterlockFlt Master interloc...

Page 429: ...2 connector panel is assigned to be the LSB of the input azimuth angle then TTL CMOS on J1 splConfig Io62 0 Opt Cp J1 pin01 sPedAZ 0 The notation indicates that no assignment is made BNC testpoint mon...

Page 430: ...For more information on testing and backing up the system components see 1 2 Related Documents page 13 RVP900 User Guide M211322EN J 428...

Page 431: ...logically possible More Information Regulatory Compliances page 16 G 2 RCP903 ASR9 WSP Panel Regulatory Compliances Table 124 RCP903 ASR9 WSP Panel Regulatory Compliances Listing Standard Electrical...

Page 432: ...icates normal operation when illuminated When blinking shows unit is operational but not running data When ON solid indicates operational and running data LED behavior backward compatible with RVP7 be...

Page 433: ...sign used an embedded general purpose computer built by Ampro Corporation that utilized an ISA bus to connect to the ASR9 specialized radar interface module RIM hardware The hardware was implemented i...

Page 434: ...Figure 68 ASR9 WSP with RVP7 Architecture RVP900 User Guide M211322EN J 432...

Page 435: ...connection to the Mercury computer have been obsoleted and the I Q data path for the ASR9 will now pass to the RVP902 WSP Processor over Ethernet on J5 The required trigger and header information is...

Page 436: ...WSP RVP902 WSP Processor Computer RVP900 Signal Processor RCP903 Panel Assembly for ASR9 WSP RDA900 Software RVP900 RVP905 Manual Set G 4 1 RVP901 WSP Signal Processor Customized for ASR9 WSP The RVP9...

Page 437: ...the RVP900 I Q data with the ASR9 data stream AC Power option 24V Fan G 4 2 RVP902 WSP Processor Customized for ASR9 WSP RVP902 WSP Processor is Vaisala s standard product offering with a Xeon X8DTU m...

Page 438: ...ugh functionality Pre trigger and tagging interface to RVP901 WSP 24V DC supply input 1 A max current 8 Indicator LEDs Backward compatible 2x 6 Level weather indicators and 4x test LEDs 2x RCP903 stat...

Page 439: ...sions The mounting dimensions of the RCP903 ASR9 WSP Panel are 1U 19 in a EIA rack The RCP903 solution includes a 1U shelf mounted directly behind the panel The rear mounting shelf includes a connecto...

Page 440: ...View G 5 2 ASR9 WSP Connector Locations All the connectors on the RCP903 ASR9 WSP Panel that interface with the radar are on the front of the mounting position Figure 77 RCP903 ASR9 WSP Panel G 5 3 RC...

Page 441: ...r Designs REL 110 1006 WT CHCO 115 VAC IN 24VDC Ethernet switch MOXA EDS G205 T or EDS G205 1GTXSFP T CBL210355 Cable DC RCP903 Shelf DC Supply RCP903 G 6 RCP903 ASR9 WSP Electrical Interfaces Figure...

Page 442: ...en the twisted signal pairs to maintain signal integrity guarantee valid logic levels on TTL signals and low noise analog signal are provided by Vaisala The current cable meets the MIL DTL 22759 11 sp...

Page 443: ...sample input J14 VIDEO OUT SMA Video DAC output J15 TRIG A SMA General purpose trigger I O or DAFC interface Figure 80 Vaisala Supplied Bay 4 G 6 3 RCP903 ASR9 WSP Panel Interfaces Table 129 RCP903 A...

Page 444: ...is solid green and RCP indicator is blinking red STATUS Between J4 and J5 Green LED 1 2 3 4 Between J6 and J7 Green LED Programmable to display ASR9 WSP test or debug status DIAG Between J5 and J6 Mo...

Page 445: ...atus 26 10 27 28 WP_BEAMS RS 422 Output Beam Selection 43 27 29 30 WP_AHI_L_P N RS 422 Input A Hi Beam Status 11 44 31 32 WP_BHI_L_P N RS 422 Input B Hi Beam Status 28 12 33 34 WP_STC05_P N RS 422 Out...

Page 446: ...t Spare 24 8 21 22 WP_026MHZ_CLK RS 422 Input 2 6 MHz Clock 41 25 23 24 NC_WP_SPARE8_P N Spare No Connect Spare 9 42 25 26 WP_103MHZ_CLK RS 422 Input 10 32 MHz Clock 26 10 27 28 WP_ACP_P N RS 422 Inpu...

Page 447: ...rface RJ45 Ethernet Interface provides 100 1000 Base T communication with RVP902 WSP Processor direct or through a network switch This interface requires Jumbo Frames RJ 45 signal interface cable side...

Page 448: ...1 19 DIFF0 P N 2 23 IFDR_HDR_INFO 0_P N TTL 5V Output 2 20 DIFF1 P N 3 24 IFDR_HDR_INFO 1_P N TTL 5V Output 3 21 DIFF2 P N 4 25 IFDR_HDR_INFO 2_P N TTL 5V Output 4 22 DIFF3 P N 5 26 IFDR_HDR_INFO 3_P...

Page 449: ...6 47 AMUX1 P N 57 58 V_1PO ANALOG Output 50 51 AMUX2 P N 43 44 IFD_PRESENT TTL 5V Input 44 45 5V GND 45 46 NC_V_N5PO ANALOG No Connect 48 49 5V GND 62 GND GND Output 18 GND G 6 10 J7 Power Interface D...

Page 450: ...functions marked with a allow monitoring of board status and manufacturing tests Commands that are no longer needed because those physical interfaces no longer exist have been deprecated See Table 146...

Page 451: ...ne state rim_sio_setclock Sets the baud rate and clock phase of the 6 level weather interface rim_sio_setidle Sets the idle pattern of the 6 level weather interface rim_sio_sendbuf Sends data to be tr...

Page 452: ...clk_status Gets the current status of the ASR9 and RCP903 clocks Table 142 RIM API Azimuth Functions Function Name Description rim_asr9_getaz Gets the current antenna position and rotation count Table...

Page 453: ...of the antenna signals WP_ACP WP_ARP rim_asr9_simiq Sets the simulation state of the I Q data rim_asr9_simiq_get Gets the simulation state of the I Q data srim_asr9_simiq_data_get Gets the simulation...

Page 454: ...tionality exists in the light weight remote procedure call routines lwrpc IO functions rim_port_init rim_port_read rim_port_write rim_pld_serial rim_board_allow Hardware interface no longer exists Mem...

Page 455: ...Appendix H TDWR Customizations H 1 TDWR Technical Drawings Figure 81 J1 to J9 Wiring Diagrams Appendix H TDWR Customizations 453...

Page 456: ...Figure 82 J90 to J111 Wiring Diagrams RVP900 User Guide M211322EN J 454...

Page 457: ...Figure 83 J13 Wiring Diagram Appendix H TDWR Customizations 455...

Page 458: ...ed with an optional custom back panel that connects to the specific electrical signals of the FAA Terminal Doppler Weather Radar TDWR The back panel connects to the two IFDR 51 pin micro D I O connect...

Page 459: ...GND Command RF Pilot Pulse Switch 4 17 TTL Out RFTSTTER GND Command RF Test Term Switch 5 18 TTL In RFXTALFM GND Status Crystal Fault Monitor 25 GND Common Ground Table 148 J2 Filter Amp 2 Pin Type D...

Page 460: ...BDCLK STCBDCLKn STC Serial Loadup Clock 25 GND Common Ground Table 152 J6 STC 2 Pin Type Direction Signal Name Comment 6 19 RS 422 Out STCDATA STCDATAn STC Serial Loadup Data 7 20 RS 422 In TRLFLT TRL...

Page 461: ...EX5VB REX5VBn REX 5V Power Monitor 2 9 11 Analog In REX18VA REX18VAn REX 18V Power Monitor 1 22 24 Analog In REX18VB REX18VBn REX 18V Power Monitor 2 25 GND Common Ground More Information TDWR Technic...

Page 462: ...the following Common Direct connections using the Common I O model TDWR MIT LL TDWR custom breakout panel and protocols If you change this run softplane resave to rev the choices splConfig Rvp9 0 sNe...

Page 463: ...d be one of the following Direct Direct I O with IO62 connector itself IO62CP Standard IO62 CP connector panel RCP88D RCP8 portion of WSR88D panel RVP88D RVP8 portion of WSR88D panel splConfig Io62 0...

Page 464: ...2 0 Opt Cp J4 pin20 TTL CMOS on J5 splConfig Io62 0 Opt Cp J5 pin01 cEarthEL 0 splConfig Io62 0 Opt Cp J5 pin02 cEarthEL 1 splConfig Io62 0 Opt Cp J5 pin03 cEarthEL 2 splConfig Io62 0 Opt Cp J5 pin15...

Page 465: ...J3_05_18 pinPos sPWidth 0 splConfig Io62 0 Opt Cp J3_05_18 pinNeg sPWidth 1 splConfig Io62 0 Opt Cp J3_06_19 lRS422 0 splConfig Io62 0 Opt Cp J3_06_19 iTerm 1 splConfig Io62 0 Opt Cp J3_06_19 pinPos...

Page 466: ...07_20 pinNeg Relays and relay drivers on J6 splConfig Io62 0 Opt Cp J6_IntRelay1 cPWidth 0 splConfig Io62 0 Opt Cp J6_IntRelay2 cPWidth 1 splConfig Io62 0 Opt Cp J6_IntRelay3 splConfig Io62 0 Opt Cp J...

Page 467: ...y Phase Diversity Techniques Preprints of the 27th Conference on Radar Meteorology American Meteorological Society 770 772 Sachidananda M D S Zrni and R J Doviak 1997 Signal Design and Processing Tech...

Page 468: ...RVP900 User Guide M211322EN J 466...

Page 469: ...he radar and signal processor azimuth A direction in terms of the 360 compass North at 0 east at 90 south at 180 and west at 270 BITEX Built in test equipment software provided by IRIS burst channel C...

Page 470: ...omputed by the signal processor The standard deviation of the Doppler spectrum is the spectrum width in m s double conversion Received signal frequency is down converted in two steps first to higher i...

Page 471: ...t is nearly linearly proportional to the rainfall rate LDR Depolarization ratio Ratio between the reflectivity received at vertical polarization but transmitted with horizontal polarization and the re...

Page 472: ...ons See also FFT page 468 RAW product Spherical coordinate data product obtained directly from the raw ingest data The data are stored in compressed format so they can be recorded on tape or sent to a...

Page 473: ...ignal to noise ratio STALO Stable Local Oscillator A very stable radio frequency local oscillator used in radar for mixing received signals to produce an intermediate frequency signal STAR mode Simult...

Page 474: ...track 28 BPHUNT 312 BPOPTS 323 hunt 177 312 processing 323 setup 350 timing adjust 136 tracking 177 burst pulse analysis amplitude 42 frequency 42 phase 42 burst spectra 137 C calibration 362 clutter...

Page 475: ...e 151 ambiguity spectra plot 160 burst pulse alignment 28 burst pulse timing 132 134 135 burst pulse timing adjust 136 burst pulse timing plot 132 burst spectra plot 137 clock subsystem 63 65 compress...

Page 476: ...noise level sample 252 SNOISE 252 noise levels 116 nomenclature 19 NOP 237 O opcode custom opcodes 323 USRCONT 323 USRINTR 323 XARGS 306 opcodes activity 374 operating parameters SOPRM 239 P performan...

Page 477: ...ace test points 127 RCP903 ASR9 WSP panel 429 architecture 431 China RoHS 16 custom panel 435 dimensions 436 electrical interfaces 439 ethernet interface 445 indicators 442 interconnect cabling 439 in...

Page 478: ...92 factory 88 IFDR 93 102 104 113 122 126 127 modify 92 modulations 126 phase control 102 126 saved 88 transmissions 126 triggers 113 Tx Synthesis 122 SIG 206 signal generator algorithm testing 231 si...

Page 479: ...mple 401 record data format 413 record on local RVP example 402 record on separate host example 402 required software 393 showCPIs 376 signal processing 183 simulated data 289 software architecture 38...

Page 480: ...2 view card 89 system status 89 Vp 91 W warranty hardware waveform 152 waveforms trigger generator 293 weather Signal Power autocorrelation 206 threshold 206 weather signal processing 40 wide dynamic...

Page 481: ...ntability or fitness for a particular purpose For standard warranty terms and conditions see www vaisala com warranty Please observe that any such warranty may not be valid in case of damage due to no...

Page 482: ...RVP900 User Guide M211322EN J 480...

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Page 484: ...www vaisala com...

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Vaisala RVP900, User Manual, Page: 27 / 484

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