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Vaisala RVP900 User Manual

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M211322EN-J

User Guide

RVP900 Digital Receiver and Signal Processor

RVP900

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Page 1 M211322EN-J User Guide RVP900 Digital Receiver and Signal Processor RVP900...
Page 2 This product contains software developed sold or disclosed to a third party without by Vaisala or third parties. Use of the prior written permission of the copyright software is governed by license terms and holder. Translated manuals and translated...
Page 3: Table Of Contents
Open Hardware and Software Design............37 3.2.3 RVP902 Socket Interface................37 3.2.4 RVP902 Socket Protocol................38 3.2.5 Public API....................40 RVP900 Weather Signal Processing..............40 3.3.1 Burst Pulse Analysis for Amplitude, Frequency, and Phase....42 3.3.2 Time (Azimuth) Averaging................43 3.3.3 TAG Angle Samples of Azimuth and Elevation........43 3.3.4...
Page 4 5.2.8 M+ Debug Options..................127 Plot-assisted Setups..................129 Plot-assisted Setup Overview................ 129 Plot Command Conventions................129 Configuring RVP900 Digital Front End............130 P+ — Plot Test Pattern..................131 Pb — Plot Burst Pulse Timing.................132 6.5.1 Interpreting the Burst Timing Plot............132 Pb Subcommands..................134 6.5.2...
Page 5 RVP Algorithm Overview................169 7.1.1 Measured Quantities.................170 7.1.2 IF Signal Conversion Process..............171 IF Signal Processing..................172 7.2.1 FIR (Matched) Filter.................. 172 7.2.2 RVP900 Receiver Modes................174 7.2.3 Automatic Frequency Control (AFC)............176 7.2.4 Burst Pulse Tracking..................177 7.2.5 Interference Filter..................178 7.2.6 Large-Signal Linearization................ 181 7.2.7...
Page 6 RVP900 User Guide M211322EN-J Dual PRT Processing Mode................220 7.7.1 DPRT-1 Mode....................221 7.7.2 DPRT-2 Mode.................... 222 Dual PRF Velocity Unfolding................. 222 Random Phase Second Trip Processing............226 7.9.1 Random Phase Second Trip Processing Algorithm......227 7.9.2 Tuning for Optimal Performance............229 7.10...
Page 7 Table of Contents Technical Data....................329 Signal Processing....................329 RVP900 Processing Algorithms..............329 RVP900 Input and Output Summary............330 RVP901 IFDR Specifications................331 RVP901 Digital Waveform Synthesis............333 RVP902 Signal Processing Computer Specifications........ 334 RVP902 Safety Compliance................335 RVP900 Spare Parts..................336 Physical and Environmental Characteristics..........336 9.10...
Page 8 TS Recording on Separate Archive Host..........402 D.7.4 TS Playback on a Local RVP900............404 D.7.5 TS Playback from a Separate Archive Host to an RVP900....405 D.7.6 TS Archive Recording Quick Guide............406 D.7.7 TS Archive Playback Quick Guide............406 Ascope Playback Features................406...
Page 9 Appendix G: RCP903 ASR9-WSP Panel............429 ASR9-WSP with RCP903 ASR9-WSP Panel Overview......429 RCP903 ASR9-WSP Panel Regulatory Compliances.........429 Power Conditions for Use - RCP903 ASR9-WSP........430 ASR9 WSP with RVP900 Panel Architecture..........431 G.4.1 RVP901-WSP Signal Processor Customized for ASR9 WSP....434 G.4.2 RVP902-WSP Processor Customized for ASR9 WSP......
Page 10 RVP900 User Guide M211322EN-J List of Figures Figure RVP901 IFDR....................... 21 Figure 2 IF to I/Q Processing Steps................22 Figure 3 Calibration Plot for RVP901................25 Figure 4 Digital IF Band Pass Design Tool..............27 Figure 5 Burst Pulse Alignment Tool................28 Figure 6 Received Signal Spectrum Analysis Tool...........
Page 11 Figure 65 TS Playback on Local RVP900..............404 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 Architecture............434 Figure 70 Top Panel Dimensions...................436...
Page 12 Pr TTY Information Lines................159 Table 41 Pa Subcommands................... 163 Table 42 Ps TTY Information Lines................164 Table 43 Algebraic Quantities Within the RVP900 Processor......170 Table 44 Receiver Mode Configuration Options............174 Table 45 Algorithm Results for +16 dB Interference..........179 Table 46 Impact of False Alarms on Reflectivity Estimates........179...
Page 13 PROC Modes.....................256 Table 68 PROC 8-bit and 16-bit Data Formats............258 Table 69 TSOUT Random Phase Major Mode Values..........264 Table 70 RVP900 Status Output Words..............271 Table 71 Data Returned by RBACK................304 Table 72 Signal Processing....................329 Table 73 Processing Algorithms.................. 329 Table 74 I/O Summary....................
Page 14 Table 120 Configuration Requirements for IRIS Playback........408 Table 121 TS File Format....................413 Table 122 Internal BITE Packet (RVP900 to Host)............ 417 Table 123 Internal QBITE Packet (RVP900 to Host)..........422 Table 124 RCP903 ASR9-WSP Panel Regulatory Compliances......429 Table 125 RVP900-WSP Components ...............
Page 15: About This Document
Radar Control Processor RCP8 User Guide For information on changes made since your current release was installed, download the latest document versions and check the IRIS and RDA Release Notes from www.vaisala.com. Vaisala encourages you to send your comments or corrections to...
Page 16: Documentation Conventions
Indicates that you need to take some notes during the task. 1.4 Trademarks Vaisalaâ is a registered trademark of Vaisala Oyj. Digi TransPortâ is a registered trademark of Digi International Inc. All other product or company names that may be mentioned in this publication are trade...
Page 17: Product Overview
Chapter 2 – Product Overview 2. Product Overview 2.1 RVP900 Product Architecture RVP900 provides a full suite of weather radar signal processing functionality to support implementing a new weather radar or upgrading an existing system to the latest signal processing technology. The flexible architecture provides modular, highly configurable hardware, and an open software design with public APIs that support developing applications and algorithms using RVP900 as a foundation.
Page 18: Regulatory Compliances
2.2.1 WEEE Compliance DECLARATION OF CONFORMITY in relation to Directive 2002/96/EC, Waste Electrical and Electronic Equipment (WEEE). RVP900 and RVP900-WSP manufactured by Vaisala comply fully with the requirements of Directive 2002/96/EC on the Waste Electrical and Electronic Equipment (WEEE). 2.2.2 RoHS Compliance The RoHS Directive 2002/95/EC restricts the use of six hazardous materials found in electrical and electronic products.
Page 19 Chapter 2 – Product Overview RVP9IFD China RoHS Compliance RVP901-AC and RCP903 China RoHS Compliance...
Page 20: Safety
RVP900 User Guide M211322EN-J 2.3 Safety WARNING! Turn off power to the main chassis before installing or removing PCI boards. Disconnect the line cord should be disconnected before opening either the IFD module or main chassis. WARNING! If IFDR is equipped with AC power option and installed in a 220V application, a fuse must be included in the neutral input path of the end product for compliance with IEC 60601-1:2005.
Page 21: Esd Protection
Chapter 2 – Product Overview 2.3.1 ESD Protection Electrostatic Discharge (ESD) can damage electronic circuits. Vaisala products are adequately protected against ESD for their intended use. However, it is possible to damage the product by delivering electrostatic discharges when touching, removing, or inserting any objects in the equipment housing.
Page 22 RVP900 User Guide M211322EN-J...
Page 23: Functional Description
3.1 RVP901 IF Digital Receiver The RVP Intermediate Frequency Digital Receiver (IFDR) receives and digitizes the IF signal. The resulting digital I and Q data is sent to the RVP900 software on the radar server computer processing into data products. 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.
Page 24: Rvp901 Ifdr Data Capture And Timing
RVP900 User Guide M211322EN-J Figure 2 IF to I/Q Processing Steps More Information ‣ RVP900 Product Architecture (page 15) ‣ RVP901 IFDR Hardware (page 54) ‣ RVP901 IFDR Specifications (page 331) ‣ RVP901 IFDR Technical Drawings (page 369) 3.1.1 RVP901 IFDR Data Capture and Timing RVP901 IFDR handles digital input and output, such as triggers, polarization switch controls, and pulse width control.
Page 25: Rvp901 Ifdr If To I And Q Processing
COHO on a traditional Klystron system, it is the master time keeper. The RVP901 IFDR sample clock is used to phase lock the entire RVP900: the Rx, Tx, miscellaneous I/O are phase-locked to the IFDR sample clock. It is programmable over a wide range of frequencies.
Page 26 80 microseconds compressed pulse, whose transmit bandwidth was approximately 1 MHz. Finer range resolutions are also possible, down to a minimum of 25 m. In RVP900, the bin spacing of the (I,Q) data can be set to any value between 25 ... 2000 m. Range bins are placed accurately to within +2.2 m of any selected grid, which does not have to be an...
Page 27: Figure 3 Calibration Plot For Rvp901
IF band pass filtering 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 I/Q samples from the Rx.
Page 28: Table 4 Real-Time Signal Corrections To I/Q Samples
Table 4 Real-time Signal Corrections to I/Q Samples Correction Description Amplitude correction RVP900 computes a running average of the transmit pulse power in the magnetron burst channel in real-time. Individual received I/Q samples are corrected for pulse-to-pulse deviations from this average.
Page 29: Figure 4 Digital If Band Pass Design Tool
Chapter 3 – Functional Description 3.1.3.2 Digital IF Band Pass Design Tool The digital matched filter computes I and Q interactively using a TTY and oscilloscope for graphical display. You can choose the filter's passband width and impulse response length, and RVP constructs the filter coefficients.
Page 30: Figure 5 Burst Pulse Alignment Tool
Quality assessments perform a 2D search in both time and frequency space if a valid burst pulse is undetected. 3.1.3.4 Received Signal Spectrum Analysis Tool RVP900 provides plots of the IF signal versus range as well as spectrum analysis of the signal. You can perform detailed analysis and configuration from a central maintenance facility...
Page 31: Digital Transmitter Function
This signal is filtered using analog components, then up-converted to RF, and finally amplified for transmission. The transmitter can be a solid state or vacuum tube device. RVP900 can correct for waveform distortion by adaptively “pre-distorting” the transmit waveform, based on the measured transmit burst sample.
Page 32: Table 5 Example Tx/Rx Processing Algorithms
COHO synthesis RVP900 output waveform can be programmed to be a simple CW sine wave. It can be synthesized at any desired frequency and amplitude, and its phase is locked to the other system clocks.
Page 33: Magnetron Receiver Example
Chapter 3 – Functional Description 3.1.5 Magnetron Receiver Example Figure 7 Analog vs Digital Receiver for Magnetron Systems Analog Receiver - Magnetron In a typical magnetron system analog receiver, the received RF signal from the LNA is first mixed with the STALO (RF-IF). The resulting IF signal is applied to one of several band pass filters that match the width of the transmitted pulse.
Page 34 RVP Digital Receiver - Magnetron For the RVP900 digital receiver, the old parts that remain are the microwave STALO oscillator and the mixer that produces the transmit burst. The burst pulse and the analog IF waveform are cabled directly into the IFDR on SMA coax cables.
Page 35: Figure 8 Basic Magnetron System
(IFDR) The optional Digital Automatic Frequency Control (DAFC) interfaces to a digitally controlled STALO. RVP900 provides full AFC control with burst pulse auto-tracking. I/O-62 PCI Card Available for additional triggers, parallel, synchro or encoder AZ and EL angle inputs, pulse width control, spot blanking control output, and more.
Page 36: Figure 9 Dual Polarization Magnetron System
RVP900 User Guide M211322EN-J Figure 9 Dual Polarization Magnetron System RVP900 supports calculation of the complete covariance matrix for dual pol, including, for example, Z , PhiDP (K ), 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 and Receive (STAR) system, or a dual-channel switching system (co- and cross-receivers).
Page 37: Klystron Or Twt Receiver And Transmit Rf Example
RVP Digital Receiver - Klystron The RVP900 transmitter function plays the role of a programmable COHO. The digitally synthesized transmit waveform can be phase, frequency, and amplitude modulated (no separate phase shifter is required), and even produce multiple simultaneous transmit frequencies.
Page 38: Rvp902 Signal Processing Computer
I/Q values that are generated by the RVP901 IFDR. While available, the system does not require that a keyboard, mouse, or monitor be connected, which is typically the case at an unattended site. The RVP902 computer also hosts RVP900 utilities, for test, configuration, control, and monitoring.
Page 39: Lan Connection For Data Transfer Or Parallel Processing
GNU tools (for example, gcc, gdb, make). Using public APIs, researchers and OEM manufacturers can modify or replace existing algorithms, or write their own software using the RVP900 software as a foundation. Upgrades To support software upgrades, RVP902 can flash RVP901 software.
Page 40: Rvp902 Socket Protocol
Example: READ|100| means read 100 bytes from the RVP900. Read (READ) Since the RVP900 interface is a 16-bit word interface, these read sizes should always be even. It always replies with a Ack| followed by 100 bytes of binary data, or with a...
Page 41 This data is written to RVP900. The data size should be even. Read Status Example: STAT| reads the status bits back from the RVP900. This is a 1 bit value, set to 1 if the RVP900 has data available in its output buffer.
Page 42: Public Api
To support writing your own signal processing algorithms for RVP900, the RVP900 software architecture allows you to statically link plug-in modules to the running code. The following table shows how the API supports adding software extensions to the RVP900 framework to modify some signal processing stages.
Page 43: Figure 12 I/Q Processing For Weather Moment Extraction
Chapter 3 – Functional Description After the IFDR unit has digitized the received echo signal into samples (I and Q data), RVP processes the data in the radar server computer using computations such as: • Converting the received signal amplitude into calibrated radar reflectivity values. •...
Page 44: Burst Pulse Analysis For Amplitude, Frequency, And Phase
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 two, a DFT is performed instead of an FFT.
Page 45: Time (Azimuth) Averaging
During data acquisition and processing, it is usually necessary to associate each output ray with an antenna position. To make this task simpler, RVP900 samples 32 digital input TAG lines from the RVP data structure: once at the beginning and once at the end of each data acquisition period. These samples are output in a four-word header of each processed ray.
Page 46: Range Averaging And Clutter Microsuppression
• dBT—Identical to dBZ, but without ground clutter These standard parameters are output to the host application. 3.3.6 Threshold Processing RVP900 calculates several parameters that are used to threshold (discard) bins with weak or corrupted signals. The thresholding parameters are: • Signal quality index (SQI=|R1|/R0) •...
Page 47: Velocity Unfolding
More Information ‣ Speckle Filter Processing (page 210) 3.3.8 Velocity Unfolding The RVP900 processor can unfold mean velocity measurements based on a dual PRF algorithm. In this technique, 2 radar PRFs are used for alternate N-pulse processing intervals. The internal trigger generator automatically produces the correct dual-PRF trigger. An external trigger can also be applied.
Page 48: Table 9 Autocorrelation Mode
Autocorrelations are computed from the inverse transform. 3.3.9.1 RVP900 Pulse Pair Time Domain Processing Pulse pair processing is done by direct calculation of the autocorrelation. Prior to pulse pair processing, the input I and Q values are filtered for clutter using a time domain notch filter, frequency domain fixed, or variable width filters.
Page 49: Output Data
SNR. Magnetron radars have a naturally random phase. For Klystron radars, a digitally controlled precision IF phase shifter is required. RVP900 provides an 8-bit RS422 output for the phase shifter. 3.3.9.4 Polarization Mode Processing...
Page 50: Radar Control Functions
AZ/EL angle inputs. Phase shifter Used to control the phase on legacy Klystron systems. New or upgraded Klystron or TWT systems can use the RVP900/Tx card to provide accurate phase shifting. switch control For horizontal/vertical or other polarization switching scheme.
Page 51: Configuration And Monitoring
Chapter 3 – Functional Description 3.5 Configuration and Monitoring The radar server computer (RVP902) stores the setup configuration on a disk. You can access setup information locally or remotely, over the network. For multiple radar networks, you can manage the configuration centrally by copying tested master configuration files to the network radars.
Page 52: Digital Afc (Dafc)
3.8 Utilities and Applications RVP900 includes applications and utilities for the calibration, alignment, and configuration. These can be run locally on RVP900 or over the network from a central maintenance facility. For more information, see IRIS and RDA Utilities Guide. Table 11 RVP Utilities...
Page 53: Network Architecture
Includes features such as looping, cross-section, track, local warning, and annotation. IRIS/Analysis and IRIS/Radar include the capabilities of IRIS/Display. Any IRIS system can display products 3.9 Network Architecture RVP900 can run on a network to support remote control and monitoring, subject to the user's security restrictions.
Page 54: Figure 15 Network Architecture
M211322EN-J Figure 15 Network Architecture The dsp lib runs locally on RVP900. The DspExport utility exports the library over the network through a TCP/IP socket. Typically the controlling application is on the same computer, but DspExport can also export to a remote host radar server computer on the network.
Page 55: Rvp Hardware
• RVP902 main chassis, which is usually mounted in a 19" EIA rack Much of the RVP900 I/O is configured through software. Since there is no custom wiring, internal jumpers, or oscillators, it is easy to insert spare modules. See E.
Page 56: Rvp901 Ifdr Hardware
RVP900 User Guide M211322EN-J Figure 16 RVP900 System Concept Vaisala 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: Upgrading If Receiver With Rvp901 Ifdr
Chapter 4 – RVP Hardware The RVP901 IFDR module is typically placed where a traditional LOG receiver would be installed. The module can be mounted on edge with the 26.8 cm x 4.8 cm (10.5 in x .9 in) surface flush to the back of the receiver cabinet with 17.6 cm (6.9 in) protrusion into the cabinet.
Page 58: Rvp901 Ifdr Power, Size, And Mounting Considerations
The platform provides support for TCP and UDP packets. The default IP address, shipped with each system, is 10.0.1.254. The IFDR supports jumbo packets. Vaisala recommends the UDP packet sizes be set to 8192 on the host computer. To comply with industry standards, use a shielded CAT5e cable (certified to 350 MHz), with shielded RJ45 plugs on each end.
Page 59: Rvp901 Ifdr I/O Connectors
Chapter 4 – RVP Hardware Consideration Description Power module The power module is an auto-ranging AC-DC converter generating 24V to drive the RVP901 and external fans. The RVP901 IFDR is delivered with the power supply module attached to the IFDR mechanical housing.
Page 60: Table 15 Generic Interconnect Cable For Ifdr Analog/Digital I/O
RVP900 User Guide M211322EN-J J-ID Label Type Description J13C ADC-C Direct IF Input J13D ADC-D Direct IF Input J13E ADC-E Direct IF Input. Burst Sample Input VIDEO OUT Video DAC output, synthesizes simple video waveforms TRIG-A General purpose trigger I/O or DAFC interface Switch Tactile, momentary on switch.
Page 61 Chapter 4 – RVP Hardware D Connectors Index 37- Pin Signal Name Softplane Signal GPDIFF_PIN_LP/N Comm.diff 7/25 7/20 — GPDIFF_PIN_LP/N Comm.diff 8/26 8/21 — GPDIFF_PIN_LP/N Comm.diff 9/27 9/22 — GPDIFF_PIN_LP/N Comm.diff 10/28 10/23 — — TTLIO_PIN/GND Comm.ttl/GND 11/29 — 1/20 TTLIO_PIN/GND Comm.ttl/GND 12/30...
Page 62: Rvp901 Miscellaneous Discrete And Analog I/O Connectors
RVP900 User Guide M211322EN-J 4.2.4 RVP901 Miscellaneous Discrete and Analog I/O Connectors Table 16 Discrete and Analog I/O Function Description Misc • 2 identical 51-pin MicroD connectors to support miscellaneous I/O • Includes D/A, A/D, discrete inputs and outputs (TTL, RS-485/422, and so on.).
Page 63: Rvp901 Ifdr Status Indicators
RVP902 software but no services have been started. The red light is solid when the rvp900 service on the RVP902 server has connected and configured the unit for normal operation.
Page 64: Rvp901 Ifdr Inputs
1 nanosecond to ensure sampling in multiple channels is of the nearly equivalent targets. RVP900 provides AFC support for tuning the STALO of a magnetron system. Alternatively, the magnetron can be tuned by a motorized tuning circuit controlled by RVP900.
Page 65: Configuring The Rvp901 Ifdr Clock Subsystem
In most installations, an external, anti-alias filter is installed on both of these inputs. These filters (if supplied by Vaisala) are mounted externally on one side of the IFDR, and have an insertion loss of 0.5 dB ... 1.0 dB. Thus, the input saturation level is +8.5 dBm ... +9.0 dBm, measured at the filter inputs.
Page 66: Table 21 Clock Generator Concerns In A Synchronous Radar System
COHO signal is used in place of a sample of the transmit burst. There are two concerns that may occur when RVP900 is used in the above manner within a synchronous radar system. Both concerns are the result of the RVP901 IFDR sampling clock being asynchronous with the radar system clock.
Page 67: Table 22 Sample Clock Frequency Considerations
The solution to these concerns is to provide a way for the RVP901 IFDR internal sampling clock to be phase locked to the radar system. If RVP900 provides the radar triggers, then those triggers become synchronous with the radar COHO. If RVP900 receives an external trigger, then its range bin clock is synchronous with that external trigger, and there is no synchronization jitter in the range bins.
Page 68: Configuring External Pre-Trigger Input
If AC coupled and 50 Ω terminated, it can take a -6 ... 8 dBm input signal. This makes it easier to connect to existing high-voltage trigger distribution systems. The rising or falling edge of this external trigger signal is interpreted by RVP900 as the pretrigger point. The pulse width of the signal does not matter.
Page 69: If Bandwidth And Dynamic Range
4.2.10 IF Bandwidth and Dynamic Range RVP900 performs best with a wide bandwidth IF input signal. A wideband signal can be made free of phase distortions within the (relatively narrow) matched passband of the received signal. RVP900 uses an external analog anti-aliasing filter at each of its IF and Burst inputs.
Page 70: Figure 18 Calibration Plot For A Stand-Alone 16-Bit Ifdr
106 dB for a 2.0 μsec pulse. The following figure shows a calibration curve demonstrating this performance, for which the RVP900 digital bandwidth was set to 0.53 MHz. An external signal generator, with steps of 1 dB, was used to measure the compression and detection thresholds.
Page 71: Configuring If Gain Based On System Performance
Chapter 4 – RVP Hardware 4.2.11 Configuring IF Gain Based on System Performance When considering IF gain and system performance for a complete radar receiver, we assume that an LNA/Mixer has already been selected that offers an appropriate balance between price and noise figure. The total RF/IF gain between the antenna waveguide and the IFDR must still be determined.
Page 72 ... 8.5 dB, respectively. Each axis of the plot has an important physical interpretation within the radar system: • The horizontal axis is equivalent to the increase in the RVP900 report of filtered power when the IF-Input coax cable is connected, versus disconnected. This is an easy quantity to measure, and provides a simple way to check the overall gain of the LNA/ Mixer/IF components.
Page 73: Configuring If Gain Based On System Noise Figure
6 dB = 100 dB. 6. After assembling all of the RF and IF components, check whether you have the correct gain by verifying a 7 dB rise (independent of bandwidth) in RVP900 filtered power, when the IF- Input cable is connected and disconnected.
Page 74: Choosing Intermediate Frequency
RF/IF components and desired overall performance. 4.2.13 Choosing Intermediate Frequency RVP900 does not assume 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.
Page 75: Installing Rvp902 Main Chassis
Chapter 4 – RVP Hardware Another problem that arises with a 35 MHz IF on a magnetron system, is the RVP900 computation of AFC. If the processor cannot distinguish 37 MHz from 35 MHz, then it cannot tell the difference between the STALO being correctly on frequency, versus being 2 MHz too high.
Page 76: Installing Dafc
The RVP900 uplink transmission comes from J15 port of the IFDR. A question in the dspx sets the function of J15 port between generalized trigger function or DAFC uplink.
Page 77: Figure 21 Dafc Assembly Diagram
Chapter 4 – RVP Hardware Figure 21 DAFC Assembly Diagram DAFC Interface to STALO The DAFC module is used on RVP900 for magnetron systems to interface to a digitally controlled STALO. The DAFC is driven from the Trig-A trigger output SMA of the IFDR module.
Page 78: Table 23 Dafc Protocol Jumper Selections
AFC-16 uplink format on the pins of the 25-pin "D" connector. One of these choices must be used when the DAFC is interfaced to an RVP900 system, whose uplink uses the older style 16-bit AFC uplink format. In this case, you have to make most or all of the pin assignments using wirewrap wire to connect each bit to its corresponding pin.
Page 79: Example: Hookup To A Cti Mvsr-Xxx Stalo
Chapter 4 – RVP Hardware There is an option for having a "Fault Status" input on the "D" connector of the DAFC. Since the board is completely passive in its connection to the uplink, the fault status bit does not affect the uplink in any way.
Page 80 RVP900 User Guide M211322EN-J Bit-11 Bit-4 Bit-9 Bit-5 Bit-8 Bit-6 Bit-7 Ground Bit-12 Bit-13 Inhb First configure the IFD pins: • Pins 1 and 24 are power supply grounds, and are connected with wirewrap wire to the nearby ground posts.
Page 81: Example: Miteq Mfs-05.00- 05.30-100K-10Mp Stalo
Chapter 4 – RVP Hardware 4.4.2 Example: MITEQ MFS-05.00– 05.30–100K–10MP STALO The electrical interface for this STALO uses a 25-pin “D” connector with the pin assignments. Table 25 Pinout for the MITEQ MFS–xx.xx–xx.xx–100K–xxMP Synthesizers Ribbon Pin "D" Pin Function Ribbon Pin "D" Pin Function Ground Ground...
Page 82: Using The Legacy Ifd Coax Uplink
RVP900 User Guide M211322EN-J AFC span– [-100%,+100%] maps into [ 1330 , 1830 ] AFC format– 0:Bin, 1:BCD, 2:8B4D: 2, ActLow: NO AFC uplink protocol– 0:Off, 1:Normal, 2:PinMap :2 PinMap Table (Type 31 for GND, 30 for +5) Pin01:GND Pin02:GND...
Page 83: Figure 22 Recommended Receiving Circuit For The Coax Uplink
Chapter 4 – RVP Hardware Coax Received Max913 Uplink or equiv. Input Signal Figure 22 Recommended Receiving Circuit for the Coax Uplink The uplink signal shown in the following figure is periodic at the radar pulse repetition frequency, and conveys two distinct information types to the IFDR. The signal is normally low (to minimize driver and termination power), but begins a transition sequence at the beginning of each transmitted pulse.
Page 84: Table 26 Bit Assignments For The Ifdr Coax Uplink
(128/f is the acquisition clock frequency given in the Mc section of the RVP900 setup menu. For the default clock frequency of 71.9502 MHz, the period of the serial data is 1.779 μsec. The logic that receives the serial data should first locate the center of the first data bit at (0.5 ×...
Page 85 PLL clock ratio, and the Positive/Negative deviation sign of the Voltage Controlled Crystal Oscillator (VCXO). This format is commonly used with klystron systems, especially when the RVP900 is locking to an external trigger. --------------------------------------------------------------- |Pos| Numerator –...
Page 86: Table 27 Digital Afc Pinmap Commands
RVP900 User Guide M211322EN-J Commands #1, #2, and #3 control the 25 output pin levels of the DAFC board. These transmissions may be interspersed with the PLL-16 format in systems that require both clock locking and AFC, for example, a dual- receiver magnetron system using a digitally synthesized COHO.
Page 87 Chapter 4 – RVP Hardware Command Data Value Description CMD=4 Data<4:0> Bits <4:0> configure the on-board noise generator, so that it adds a selectable amount of dither power to the A/D converters. This noise is bandlimited using a 10-pole lowpass filter, so most of the energy is in the 150 ...
Page 88 RVP900 User Guide M211322EN-J...
Page 89: Tty Non-Volatile Setups
Chapter 5 – TTY Non-volatile Setups 5. TTY Non-volatile Setups 5.1 Using the TTY Setup Menu You can view and modify most RVP900 operating parameters with the TTY setup menu. For example: • Make TTY connections • Save and restore configurations For example, you can configure custom trigger patterns, pulse width control, matched FIR filter specs, PRF, and so on, in the field.
Page 90: Factory, Saved, And Current Settings
RVP900 User Guide M211322EN-J 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 must exit the menus using the Q before resuming normal RVP operation.
Page 91: And Vz - View Card And System Status
-------------------------------- RVP9 Digital IF Signal Processor V13.1(Pol) IRIS–8.13.1 The displayed version of RVP900 code was the last to write into the non-volatile RAM. It is printed only if that last version was different from the version that is currently running.
Page 92 RVP9/Main/Site:MonApr216:01:12EDT2012 RVP9/Proc/Core:MonApr216:01:14EDT2012 RVP9/Proc/Open:MonApr216:01:16EDT2012 RVP9/Proc/Site: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 IFDR module. The number is the present output level in D-Units ranging from -100 to +100.
Page 93: Vp - View Processing And Threshold Values
5.1.3 Vp – View Processing and Threshold Values The Vp command displays internal parameters that affect moment processing within RVP900. This information is for inspection only, and cannot be changed from the TTY. The threshold parameters are LOG (receive power above noise), CSR, weather signal power (WSP), SQI, and Polarimetric Met Index (PMI).
Page 94: Displaying And Changing Current Major Mode
5.1.4 @ - Displaying and Changing Current Major Mode The @ command provides developers with a simple way of switching modes enabling on– the–fly testing of code. For information on the top level RVP900 see SOPRM command word #9 in 8.4 Setup Operating Parameters (SOPRM) (page 239).
Page 95: Mb - Burst Pulse And Afc
Depending on the chosen sideband, an increase in microwave frequency may increase (STALO below transmitter) or decrease (STALO above transmitter) the receiver's intermediate frequency. This parameter influences the sign of the Doppler velocities computed by RVP900. IF increases for an approaching target: YES...
Page 96 ADC channel. Use the same channel for Rx and Burst Pulse Sampling: NO The PhaseLock parameter controls if RVP900 locks the phase of its synthesized I and Q data to the measured phase of the burst pulse. • Type YES for an operational magnetron system, since the transmitter's random phase must be known to recover Doppler data.
Page 97: Table 29 Analysis Window Options
Chapter 5 – TTY Non-volatile Setups Table 29 Analysis Window Options Option Recommended Use Rectangular Included as a teaching tool. Do not use for operation. Hamming Best overall choice. Blackman Useful for seeing plotted spectral components more than 40 dB below the strongest signal present.
Page 98 AFC loop begins running. In general, the AFC feedback loop is active only when RVP900 is not processing data rays. This is because the Doppler phase measurements seriously degrades when the AFC control voltage makes a change.
Page 99 Option (page 101) AFC Output Process The RVP900 AFC implementation has been generalized so that there is no difference between configuring an analog loop and a digital loop. The AFC feedback loop parameters are set the same way in each case.
Page 100: Table 30 Afc Output Process For Internal Afc Feedback
The standard RVP900/DAFC module only supports the selection of pins 1, 3, 4, 13, 14, and 25 as inputs. This setup parameter allows you to choose any pin, however, because it does not know what hardware may be listening on the uplink and what its constraints might be.
Page 101 Chapter 5 – TTY Non-volatile Setups Burst Parameters If the frequency of the transmit burst increases when the AFC control voltage increases, type Yes. Otherwise type No. When the following parameter is set correctly, a numerical increase in the AFC drive (D– Units) results in an increase in the estimated burst frequency.
Page 102 Enable burst power based correction of Z0: NO Simulated Burst Samples RVP900 can simulate a 1 µsec envelope of burst samples. Use this as a testing and teaching aid only. Never use this in an operational system. A two–tone simulation is produced when RVP900 is in dual–receiver mode. The pulse is the sum of 2 transmit pulses at the primary and secondary intermediate frequencies.
Page 103 Chapter 5 – TTY Non-volatile Setups Frequency span of simulated burst: 27.00 MHz to 32.00 MHz More Information ‣ Automatic Frequency Control (AFC) (page 176) ‣ Digital AFC (DAFC) (page 50) 5.2.1.1 AFC Motor and Integrator Option The AFC Servo– 0:DC Coupled, 1:Motor/Integrator question selects whether the AFC loop runs in the normal manner (direct control over frequency), or with an external Motor/Integrator type of actuator.
Page 104: Mc - Top-Level Configuration
AFC parameters (minimum slew, maximum slew, feedback slope) all resume working properly. The algorithm operates as follows: 1. When AFC correction is applied, RVP900 calculates how long it would take to reach the desired IF frequency at the present rate of change.
Page 105 This setting is used to configure the input of live antenna angles. If angle data are supplied outside RVP900, for example by an RCP8 making direct calls to the IRIS antenna library, then select None. For test purposes, the SimRVP and SimIFD options implement an antenna simulator either in the host computer or the remote IFDR.
Page 106: Mf - Clutter Filters
TAG offsets (degrees) AZ:0.00 EL:0.00 For example, assume the elevation angle input to RVP900 is in an awkward form such as 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 format.
Page 107 Chapter 5 – TTY Non-volatile Setups Default residual clutter LOG noise margins: Baseline : 0.15 dB/dB for Clutter/Noise above 10dB HiSignal : 1.00 dB/dB for Clutter/Noise above 50dB For example, if we observe 20 dB of total power above receiver noise, and then apply a clutter correction of 19 dB, we are left with an apparent weather signal power of +1 dB above noise.
Page 108 RVP900 User Guide M211322EN-J Variable Width, Single Slope (Type 1) RVP900 supports variable-width, frequency-domain clutter filters. These filters perform the same spectral interpolation as the fixed–width filters, except that their notch width automatically adapts to the clutter. The filters are characterized by the Width and EdgeMinPts parameters in the Mf menu, except that the Width is now interpreted as a minimum width.
Page 109: Mp - Processing Options
Maximum KEY phase error: 12.0 deg 5.2.4 Mp — Processing Options When RVP900 computes power spectra, the time series data are multiplied by a (real) window before computing the Fourier Transform (DFT). You can select the window through SOPRM word #10 0:User, or force a particular window: •...
Page 110 RVP900 User Guide M211322EN-J Ascope uploads the R2 algorithms button setting in the block Gen Setup. At RVP900 start up, the user setting is retrieved from rvp9NV.opprm.iflags. R0/R1/R2 Processing– 0:Never , 1:User, 2:Always : 1 Clutter Microsuppression The following parameter controls whether "cluttery" bins are rejected before being averaged in range.
Page 111 Chapter 5 – TTY Non-volatile Setups The following parameter allows you to choose if RVP900 attempts to run its standard processing algorithms, even when a custom trigger pattern has been selected through the SETPWF command. Usually, this does not make sense, so the default setting is 0:Never.
Page 112 IFD Wide Dynamic Range Parameters Channel separation: 20.00 dB, 0.0 deg Maximum deviation : 0.50 dB, 5.0 deg Overlap/Interpolate interval: 30.00 dB Interface Filter and Unfolding RVP900 can optionally apply an interference filter to remove impulsive-type noise from the demodulated (I,Q) data stream. See 7.2.5 Interference Filter (page 178).
Page 113 DB_FLAGS data parameter. Each threshold is specified in decibels. • The fundamental RVP900 operating parameters (PRF, Sample 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.
Page 114 RVP900 User Guide M211322EN-J Polarimetric Power Params – NoiseCorrected:YES Polarimetric Correlations – NoiseCorrected:YES You can configure the sign and offset corrections to correct for intervening weather attenuation. It uses the change of angle in DP. The tuning numbers are taken from the dualpol.conf file.
Page 115: Mt - General Trigger Setups
Normally this is set automatically by the controlling application. Melting height: 3000 meters Noise Correction If the noise correction is set to Yes, RVP900 adjusts the calibration reflectivity value Z0 when the current noise level changes from the level measured when the calibration was done.
Page 116 RVP900 trigger outputs. Answer YES if the transmitter can continue running even if the RVP900 TRIGIN signal is removed. This information is used by the L and R subcommands of the Pb plotting command, that is, when slewing left and right to find the burst pulse, the pretrigger delay is affected rather than the start times of the six output triggers.
Page 117 177). The trigger outputs are defined by: • Which RVP900 trigger outputs are timed relative to the transmitter pre–fire sequence You can move these triggers left/right using the L/R keys in the Pb plot. These triggers are also skewed in response to Burst Pulse Tracking. See 7.2.4 Burst...
Page 118: Mt - Triggers For Pulsewidth N
The RVP900 range selection compensates for the additional waveguide length to within plus–or–minus half a bin, and works properly at all range resolutions.
Page 119 High:NO Some subtleties of these variable start times are: • The PRT multipliers can only be used with the RVP900 internal trigger generator. The PRT–relative start times are completely disabled when an external trigger source is chosen from the Mt menu.
Page 120: Table 31 Prf Protection Limits Considerations
This parameter adjusts the delay from the active edge of the external trigger to range zero. This delay must be correct when RVP900 operates with an external trigger, since the zero range point is a fixed time offset from that trigger. When the transmitter is driven from the internal trigger signals, the signals are adjusted to accomplish the alignment of range zero.
Page 121: Table 32 Filter Length Considerations
Limits: 6 MHz ... 72 MHz Tx Intermediate Frequency: 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 response length: 1.33 usec Table 32 Filter Length Considerations...
Page 122 3.8 km (25.3 μsec) long, then the range resolution can be no less than 3.8 km/190= 20 m. At the RVP900 maximum 100 MHz AQ clock this filter requires (25.3 μsec)(100 MHz) = 2530 taps to compute, which fits within the 8000- tap limit.
Page 123 • 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 first starts, and when the RESET opcode is issued with Bit #8 set.
Page 124 When digital Tx waveforms are synthesized, the following questions appear in the Mt<n> menu after the Rx Intermediate Frequency question. In this case, each of the RVP900 four pulse widths can select a different type of transmit waveform and associated matched receiver.
Page 125 RVP900 convention. This offset question is provided so that the Tx output waveform can be shifted in time to compensate for whatever delays are present in the radar's IF/RF electronics.
Page 126 FIR data window. Hybrid pulse chained PW index RVP900 uses 3 real–valued tuning parameters to make the synthesis of complex waveforms more flexible. You can alter and fine-tune each waveform class up to 3° of freedom, making it possible for a single class (for example, the non–linear FM class) to generate a huge...
Page 127: Table 33 Linear Fm Class Examples
Chapter 5 – TTY Non-volatile Setups • Parameters #1 and #2 are the (X,Y) location of the non–linear breakpoint for the FM curve. The Time/Frequency behavior of the pulse can be drawn in a coordinate system whose abscissa ranges from -1 to +1 over the complete time duration of the pulse, and whose ordinate ranges from -1 to +1 over the complete frequency span of the pulse.
Page 128: Mz - Transmissions And Modulations
RVP900 User Guide M211322EN-J 5.2.7 Mz — Transmissions and Modulations Use these questions to configure the phase modulation codes that may be used to control the phase of a coherent transmitter. Phase Modulation Select whether the Tx waveforms synthesized by the IFDR have phase modulation applied to them.
Page 129: M+ Debug Options
This is the noise level that is assumed when simulated I and Q data are injected into RVP900 with the LSIMUL command. The noise level is measured relative to the power of a full–scale complex (I,Q) sinusoid, and matches the levels shown on the slide pots of the Ascope digital signal simulator.
Page 130 RVP900 User Guide M211322EN-J • Uplink signals are signals used on the uplink cable between the IFDR and the control panel. Available WSR98D RVP test 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-Coho-Sel...
Page 131: Plot-Assisted Setups
• Checking the spectral purity of the transmitter on a regular basis to check for unwanted noise or harmonics. RVP900 can track and modify the initial settings so that proper operation is maintained even with changes in temperature and aging of the microwave components.
Page 132: Configuring Rvp900 Digital Front End
Press % to toggle between the IF input SMA connectors on the IFDR. 6.3 Configuring RVP900 Digital Front You can use the Pb, Ps, and Pr commands to configure the RVP900 digital front end. You may run the commands at any time. The following procedure is for first-time setups.
Page 133: P+ - Plot Test Pattern
5.2.5 Mt — General Trigger Setups (page 113). 3. Use Mt0, Mt1, and so on to set the relative timing of the RVP900 triggers used by the radar. Do not worry about the absolute values of the trigger start times. Set their polarity and width, and their start times relative to each other.
Page 134: Pb - Plot Burst Pulse Timing
TTY monitor. 6.5 Pb — Plot Burst Pulse Timing For magnetron radars, RVP900 relies on samples of the transmit pulse to lock the phase of its synthesized I and Q data and to run the AFC feedback loop. Use the Pb command to adjust the trigger timing and A/D sampling window so that the burst pulse is correctly measured.
Page 135: Figure 25 Successful Capture Of The Transmit Burst
On the TTY, the overall time span from the left edge to the right edge is listed as PlotSpan. Plot RVP900 computes the power-weighted 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.
Page 136: Pb Subcommands
Triggers The lower portion of the plot shows the triggers output by RVP900. The number of triggers plotted match the number of user-defined output triggers set in the Mt menu, with Trigger #1 at the top.
Page 137: Tty Information Lines In Pb
L/l & R/r Shift the group of RVP900 triggers left or right (earlier or later in time). The lowercase commands shift in 0.025 μsec steps, and the uppercase commands shift in 1.000 μsec steps (approximately).
Page 138: Adjusting Burst Pulse Timing
PreDly:6.87) is printed instead. Shows the present value of timing slew (measured in microseconds) being applied to track the burst. The slew is 0 initially when RVP900 is first powered up, meaning that the normal trigger start times are all being used.
Page 139: Ps - Plot Burst Spectra And Afc
However, if the signal is too weak, then the upper bits of the A/D converter are wasted and noise is unnecessarily introduced. Vaisala recommends a peak signal level between -3 dBm and +4 dBm, that is, a signal that might be viewed at x2 or x4 zoom.
Page 140: Figure 26 Example Of A Filter With Excellent Dc Rejection
RVP900 User Guide M211322EN-J The first figure is an example of a single filter response plot, while the second shows a combined display of both spectra. The combined display makes it easy to compare the filter being designed with the live waveform that it is intended to selectively pass.
Page 141: Figure 27 Example Of A Filter With A Poorly Matched Filter
Chapter 6 – Plot-assisted Setups Figure 27 Example of a Filter With a Poorly Matched Filter The exact endpoints of the plot depend on which alias band the radar’s intermediate frequency falls in. For example, with a 72 MHz acquisition clock, a 30 MHz IF would imply a horizontal axis range of DC to 36 MHz, whereas a 60 MHz IF would make the range 36 MHz to 72 MHz.
Page 142: Ps Subcommands
RVP900 User Guide M211322EN-J Major marks are small downward triangles that represent integer multiples of 5 MHz; minor marks are in between and represent 1 MHz steps. The power spectrum in the example is from a system with an intermediate frequency of 30MHz.
Page 143: Table 37 Ps Subcommands
DC rejection. U/u & D/d Implement the Manual Frequency Control (MFC) override, and allow the RVP900/IFDs AFC output voltage to be manually set to any fixed level. The lower case commands make changes in 0.05 D-Unit steps, and the upper case commands use 1.0 D-Unit steps.
Page 144: Tty Information Lines Within Ps
RVP900 User Guide M211322EN-J Command Description & Saves Tx waveform and Rx filter coefficients as well as parameters defining the $IRIS_DATA/temp/pwd_<pulse_number>.dat file, usually /usr/iris_data. Files are in Octave data format. All data files contain the RVP9 clock frequency (variable RVP_clock_MHz) pulse IF frequency (variable IF_freq_MHz).
Page 145: Table 38 Ps Tty Information Lines
Chapter 6 – Plot-assisted Setups Table 38 Ps TTY Information Lines Information Line Description Navg The number of burst spectra that are averaged together prior to plotting. Larger amounts of averaging increase the ability to see subtle spectral components, but the display updates more slowly. The length of the impulse response of the matched FIR filter.
Page 146: Computing Filter Loss
RVP900 narrow-band receiver detects within its passband. The filter loss is a subtle quantity that depends on the combined characteristics of both the transmit waveform and...
Page 147 It is also very near zero as long as most of the burst energy is confined within the passband of the RVP900 filter. The filter loss increases as the bandwidth of the burst waveform increases and begins to spill out of that passband. Typical losses for a well-matched filter are in the 0.5 dB ...
Page 148 {b }. For purposes of this number of samples, but of a pure sine wave at the radar's IF. The RVP900 determines � � denote a power spectrum estimate that is derived in an identical manner using the same calculate �...
Page 149: Adjusting Plot Burst Spectra And Afc
Chapter 6 – Plot-assisted Setups certainly not the result that we desire. The remedy is to make a second pair of power measurements of the filter's response to a CW tone at the passband center. This serves to calibrate the gain of the filter, and allows us to compute a filter loss that captures the effects of spectral shape independent of overall gain.
Page 150: Figure 28 Example Of A Poorly Matched Filter
RVP900 User Guide M211322EN-J 4. Begin designing the matched FIR filter. Use the space bar to display both the filter response and the burst spectrum on the same plot. Use the Z key to shift the bursts main lobe up to the top horizontal line of the graph.
Page 151 • 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, RVP900 designs a new FIR filter from scratch, and displays the results.
Page 152: Figure 29 Example Of A Filter With Poor Dc Rejection
RVP900 User Guide M211322EN-J Example The offset error of the IFDR A/D converter is at most 10mV, that is, -27 dBm into its 50 Ω input. To achieve 90 dB of dynamic range below the converters +8 dBm saturation level, we expect usable I and Q values to be obtainable from a (sub-LSB) input signal at -82 dBm.
Page 153: Using Afc Test Mode
Chapter 6 – Plot-assisted Setups 6.6.6 Using AFC Test Mode In AFC test mode, the Ps command runs normally. AFC information is replaced with a hexadecimal readout of the present 25-bit value. Your display may look something like: Navg :3, FIR:1.33 usec (48 Taps), BW:1.000 MHz, DCGain:ZERO Freq:26.610 MHz, Pwr:64.6 dBm, AFCTest:0000207F (Bits) 1.
Page 154: Plotting Example For Pulse Width Definition, Waveform, And Filters
RVP900 User Guide M211322EN-J 6.6.7 Plotting Example for Pulse Width Definition, Waveform, and Filters The following plotting example is for 2 files with pulse width definition, waveform, and filters for pulse 0 (short CW pulse) and pulse 1 (NLFM pulse with pulse 0 chained to it).
Page 155 Chapter 6 – Plot-assisted Setups plot (time_scale(5850:5980), real(tx_chained_waveform_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("Frequency in MHz");...
Page 156: Plotting Example For Range Resolution Ambiguity
RVP900 User Guide M211322EN-J 6.6.8 Plotting Example for Range Resolution Ambiguity clear; load "pwd_1.dat"; short_pulse_filter = rx_filter_if; load "pwd_0.dat";long_pulse_filter = rx_filter_if; long_pulse_ambig = conv(tx_chained_waveform_if, long_pulse_filter); short_pulse_ambig = conv(tx_chained_waveform_if, short_pulse_filter); short_pulse_ambig_sz=size(short_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_pulse_ambig_length-1)/ RVP_clock_MHz; short_pulse_ambig_time_scale=0:1/RVP_clock_MHz:(short_pulse_ambig_length-1)/ RVP_clock_MHz; plot (long_pulse_ambig_time_scale, 10*log10(abs(long_pulse_ambig)), short_pulse_ambig_time_scale, 10*log10(abs(short_pulse_ambig)));...
Page 157: Pr - Plot Receiver Waveforms
Chapter 6 – Plot-assisted Setups 6.7 Pr — Plot Receiver Waveforms The Pb and Ps commands are used to analyze the signal that is applied to the Burst-In connector of the IFDR module. You must now use the Pr command to check the received signal that is connected to IF- In.
Page 158: Figure 30 Example Of Combined If Sample And Log Plot
At the x32 or higher zoom scales, this offset would peg the sample plot off scale. Typically the DC offset is much less than this worst case value; but RVP900 preserves the DC term in the Pr sample plot so that its presence is not forgotten.
Page 159: Figure 31 Example Of A Noisy High Resolution Pr Spectrum
Chapter 6 – Plot-assisted Setups The LOG points are computed at each possible offset within the raw IF samples. At the nominal 72 MHz sampling rate the spacing between LOG samples are a mere 4.17 m. The LOG plot gives a very detailed view of received power versus range. Of course, successive LOG points are highly correlated because successive input data intervals differ by only one sample point.
Page 160: Available Subcommands In Pr
Both plots preserve the DC component of the IF samples so that it can be monitored as part of the routine maintenance of the receiver system. This is one of the few places in the RVP900 menus and processing algorithms where the DC term deliberately remains intact. 6.7.2 Available Subcommands In Pr These subcommands change the start time and span of the IF sampling window, and alter the format of the display.
Page 161: Tty Information Lines In Pr
Chapter 6 – Plot-assisted Setups Command Description Zooms the amplitude of the IF samples by factors of two from one to 128. The LOG plots are shifted in corresponding 6 dB increments as the amplitude is zoomed up and down. The zoom level is reported on the TTY so that absolute power levels and A/D usage can be assessed.
Page 162: Pa - Plot Tx Waveform Ambiguity
However, the signal processing and waveform design required to make good use of these long transmit pulses is also much more complex. To help with this, RVP900 provides the Pa (plot ambiguity) command in which compressed transmit waveforms can be designed, studied, and optimized.
Page 163: Figure 32 Ambiguity Diagram Of A Compressed Tx Pulse
Chapter 6 – Plot-assisted Setups Figure 32 Ambiguity Diagram of a Compressed Tx Pulse Also shown in yellow and green are the Tx/Rx responses when the overall waveform is modified by a 50 KHz target Doppler shift. Real weather targets would never have such a large Doppler component, but the Pa menu allows you to study its effect anyway.
Page 164: Available Subcommands In Pa
RVP900 User Guide M211322EN-J Figure 33 Frequency, Phase and Amplitude of a Compressed Tx Pulse The figure shows that the waveform consists of a linear FM chirp that occupies about 87% of the central pulse duration. The frequency remains nearly constant in the leading and trailing edges, hence the label Non-Linear FM.
Page 165: Table 41 Pa Subcommands
Chapter 6 – Plot-assisted Setups Table 41 Pa Subcommands Command Description S/s & L/l The shorter and longer commands decrease or increase the time duration (that is, pulse width) of the transmitted pulse. The lower case commands shift in 0.05 μsec steps. The upper case commands use 1 μsec steps.
Page 166: Tty Information Lines In Ps
200 evenly spaced grid points lying between 0.9000 ... 0.9500 inclusive. After you have entered all 3 parameter spans, RVP900 begins searching for the optimum waveform. Progress messages are printed on the TTY, and the plot updates each time a better waveform is discovered.
Page 167: Bench Testing Compressed Waveforms
Hence, there is a loss in receive sensitivity when a window is applied. Given a compressed transmit waveform, RVP900 designs the appropriate mismatch Rx filter automatically, using an optimized Blackman window in all cases. Developers can also access the internal APIs directly to design any desired transmit waveform along with the associated FIR filter to receive it.
Page 168: Figure 34 Ifdr Sampling Of Optimized Compressed Tx Waveform
This verifies that the analog waveform is generated properly checks that the matched filtering on the RVP900/Rx card can deconvolve the compressed information. 1. Connect the Channel #1 or Channel #2 output of the RVP900/Tx card to the IF-Input of the IFDR.
Page 169: Figure 35 Ideal And Actual Linear -Fm Spectrum Displayed In Ps Plot
Chapter 6 – Plot-assisted Setups 4. If needed, use the Ps plotting command to examine the ideal transmit spectrum and received spectrum of compressed pulses. The following example shows a 60 MHz, 40 μsec linear FM pulse having a bandwidth of 2 MHz.
Page 170 RVP900 User Guide M211322EN-J...
Page 171: Processing Algorithms
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 × Y is computed as:...
Page 172: Measured Quantities
� * = Re �� − �� the number, that is: Arg{s*} = -Arg{s}. More Information ‣ RVP900 Weather Signal Processing (page 40) 7.1.1 Measured Quantities The following table summarizes the quantities that are measured and computed by RVP900.
Page 173: If Signal Conversion Process
Real Uncorrected Reflectivity factor 7.1.2 IF Signal Conversion Process The following figure shows the overall process by which the RVP900 converts the IF signal into corrected reflectivity, velocity, and width, including: • IF signal processing • I/Q processing and clutter filtering •...
Page 174: If Signal Processing
‣ RVP901 IFDR IF to I and Q Processing (page 23) 7.2.1 FIR (Matched) Filter RVP900 implements a digital version of the matched filter that is found in the traditional analog radar receiver. The filter length (number of taps), center frequency, and bandwidth are adjustable.
Page 175 The sums above for I and Q are computed on RVP900 using a flexible FGPA that can perform billions of sums of products per second.
Page 176: Rvp900 Receiver Modes
IF Inputs inputs using the same intermediate frequency. 7.2.2.1 Wide Dynamic Range Mode-2 When RVP900 is used as an extended dynamic range receiver, you must make some important decisions regarding setting up the RF/IF levels that drive the IFDR. Separation Value First, decide on the amount of signal level separation between the high gain and the low gain IFDR inputs.
Page 177 Chapter 7 – Processing Algorithms • The absolute minimum channel separation is equal to the total dynamic range of the receiver minus the dynamic range of a single channel of the IFDR. Generally, the total dynamic range of the receiver is set by the LNA. For example, for a 1μ...
Page 178: Automatic Frequency Control (Afc)
RVP900 analyzes the burst pulse samples from each pulse, and produces a running estimate of the power-weighted center frequency of the transmitted waveform. This frequency estimate is the basis of the RVP900 AFC feedback loop, whose purpose is to maintain a fixed intermediate frequency from the radar receiver.
Page 179: Burst Pulse Tracking
The burst pulse tracker feedback loop changes the trigger timing in response to the measured position of the burst. Timing changes are generally made only when RVP900 is not actively acquiring data, in the same way that AFC feedback is held off for similar quiet times.
Page 180: Interference Filter
For some environments, it is possible that good results can be obtained with C ; but RVP900 does not force that restriction. Two variations on the fundamental algorithm are also defined. The CFGINTF command allows you to choose algorithms to use, and to tune the 2 threshold constants.
Page 181: Table 45 Algorithm Results For +16 Db Interference
Chapter 7 – Processing Algorithms Optimum values for C and C vary from site to site, but some guidance can be obtained using numerical simulations. The results shown below were obtained when the algorithms were applied to realistic weather time series having a spectrum width = 0.1 (Nyquist), SNR = +10 dB, and an intermittent additive interference signal that was 16 dB stronger than the weather.
Page 182: Table 47 Algorithm Results For +26 Db Interference
RVP900 User Guide M211322EN-J 3.14% 1.06% 0.51% 0.54% 2.53% 0.85% 0.33% 0.35% 2.07% 0.67% 0.22% 0.23% 1.70% 0.54% 0.14% 0.15% 1.21% 0.35% 0.06% 0.06% 0.65% 0.14% 0.01% 0.01% It is important to minimize both types of errors. If too much interference is missed, then the filter does not do an adequate job of cleaning up the received signal.
Page 183: Large-Signal Linearization
When an IF signal saturates, there is still considerable information in the signal since only the peaks are clipped. The proprietary large signal linearization algorithm used in RVP900 provides an extra 3 ... 4 dB of dynamic range by accounting for the effects of saturation. This is possible because an overdriven IF waveform spends some of its time in the valid range of the converter, and it is possible to deduce information about the signal.
Page 184: Amplitude Correction For Tx Power Fluctuations
Figure 37 Linearization of Saturated Signals Above +8 dBm 7.2.7 Amplitude Correction for Tx Power Fluctuations RVP900 can perform pulse-to-pulse amplitude correction of the digital (I,Q) data stream based on the amplitude of the Burst/COHO input. The technique computes a (real valued) correction factor at each pulse by dividing the mean amplitude of the burst by the instantaneous amplitude of the burst.
Page 185: Time Series Signal Processing
Chapter 7 – Processing Algorithms When RVP900 enters a new internal processing mode (time series, FFT, PPP, and so on), the burst power estimator is reinitialized from the level of the first pulse encountered, and an additional pipeline delay is introduced to allow the estimator to completely settle. Valid corrected data are produced even when RVP900 alternates rapidly between different data acquisition tasks, for example, in a multi-function Ascope display.
Page 186: Time Series And Doppler Power Spectrum Example
Processing (GMAP) are available with dual polarization processing. Both of these clutter filters perform interpolation across the spectrum after ground clutter 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 of low PRF pulses is transmitted (for example, for 0.1°...
Page 187: Frequency Domain Processing- Doppler Power Spectrum
Chapter 7 – Processing Algorithms Figure 38 Time Series and Doppler Power Spectrum Example 7.3.2 Frequency Domain Processing- Doppler Power Spectrum The Doppler power spectrum (also known as Doppler spectrum) is the easiest way to visualize the meteorological information content of the time series. The Doppler power spectrum is obtained by taking the magnitude squared of the input time �...
Page 188: Figure 39 Typical Form Of Time Series Window
Typically a weighting function or "window" wm is applied to the input time series s mitigate the effect of the DFT assumption of periodic time series. RVP900 supports different windows such as the Hamming, Blackman, Von Han, exact Blackman, and the rectangular window for which all spectral components are weighted equally.
Page 189: Autocorrelation For Moment Estimations
Chapter 7 – Processing Algorithms More aggressive windows have lower side lobe power at the expense of a broader impulse response and an increased variance of the moment estimates. Window Width Side Lobes -M/2 Frequency Figure 40 Impulse Response of Typical Window In summary of the DFT approach and spectrum windows: •...
Page 190: Table 49 Time Domain Calculation Of Autocorrelations And Corresponding Physical Models
Since the RVP900 is a linear receiver, there is a single gain number that relates the 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 of these.
Page 191: Ray Synchronization On Angle Boundaries
For example, if RVP900 is operating at 1 KHz PRF, 20-deg/sec scan rate, 1° ray synchronization, and a sample size of 80. Then, if the LSYNC Dyn bit is set, rays consist of a full 80-pulses ending at each angle and extending back 30-pulses into the previous angle sector.
Page 192 IIR approach is no longer used in RVP900. The only mode that uses time domain filtering is the Batch mode for the low PRF pulses (subtraction of the average I and Q to remove the DC component).
Page 193: Figure 41 Fixed Width Clutter Filter Examples
Chapter 7 – Processing Algorithms Spectrum with ground clutter Remove 5 interior points Find minimum of 2 edge points Interpolate across 5 center points – Velocity Figure 41 Fixed Width Clutter Filter Examples This procedure attempts to preserve the noise level and/or overlapped weather targets. The result is that more accurate estimates of dBZ are obtained.
Page 194: Figure 42 Variable Width Clutter Filter
RVP900 User Guide M211322EN-J Spectrum with ground clutter Remove 3 interior points Use slope to extend the clutter bound- ary. Then find the minimum of the 2 edge points and interpolate. – Velocity Figure 42 Variable Width Clutter Filter In the figure, the minimum number of points to reject is set to 3. The filter starts at zero velocity and checks the slope to determine the point at which the power starts to increase.
Page 195 Chapter 7 – Processing Algorithms • If there is no clutter present, GMAP does little or no filtering. • GMAP repairs the damage to overlapped (near zero velocity) weather targets. • The DFT window is determined automatically to be the least aggressive possible to remove the clutter.
Page 196: Figure 43 Gmap Algorithm Steps
RVP900 User Guide M211322EN-J Figure 43 GMAP Algorithm Steps Table 51 GMAP Algorithm Steps GMAP Step Description Step 1: Window and DFT First a Hamming window weighting function is applied to the IQ values and a discrete Fourier transform (DFT) is then performed. This provides better spectrum resolution than a fast Fourier Transform (FFT) which requires that the number of IQ values be a power of 2.
Page 197 Chapter 7 – Processing Algorithms GMAP Step Description Step 2: Determine the Noise In general, the spectrum noise power is known from periodic noise power Power measurements. Since the receiver is linear and requires no STC or AGC, the noise power is well-behaved at all ranges. The only time that the spectrum noise power differs from the measured noise power is for very strong clutter targets.
Page 198 RVP900 User Guide M211322EN-J GMAP Step Description Step 3: Remove the Clutter The inputs for this step are the Doppler power spectrum, the assumed Points clutter width in m/s and the noise level, either known from noise measurement or optionally calculated from the previous step. First the power in the three central spectrum components is summed (DC ±1...
Page 199 Chapter 7 – Processing Algorithms GMAP Step Description Step 4: Replace Clutter Points The assumption of a Gaussian weather spectrum now comes into play to replace the points that have been removed by the clutter filter. There are two cases depending on how the noise level is determined under Step 2, that is, the dynamic noise case and the fixed noise level case.
Page 200 (Ice et al, 2004). They conclude that GMAP meets the ORDA requirements. Their study was based on a built-in simulator that is provided as part of the RVP900 and the Ascope utility. The simulator allows users to construct Doppler spectra, process them and evaluate the results (Sirmans and Bumgarner, 1975).
Page 201: Autocorrelation R(N) Processing
Chapter 7 – Processing Algorithms Figure 44 GMAP Example 7.4 Autocorrelation R(n) Processing 7.4.1 Point Clutter Remover Point Clutter is a target that has strong total power in one or two successive range bins but is bordered on either side in by bins of significantly lower power. These are usually non- meteorological targets such as airplanes, ships, or other moving objects.
Page 202: Range Averaging And Clutter Microsuppression
Range averaging can be performed over 2, 3, ..., 16 bins. This reduces the number of bins in the final output to save processing both in the RVP900 and in the host computer. This is accomplished by averaging the T and R values.
Page 203: Table 52 Terms In The Db Equation Format
As long as the system sensitivity (noise figure) does not change, then the system does not require re-calibration. Calibrating RVP900 involves defining the radar constant C and measuring the value of I 7.6 Reflectivity Calibration (page 214).
Page 204 � ar: Gaseous Attenuation Correction This term accounts for gaseous attenuation. Term The constant a is set in the RVP900 EEPROM since it is a function of wavelength. For a C-band system the default value is 0.016 dB per km (for two-way path attenuation).
Page 205: Velocity
+ ΔV which is 2V away from the true mean velocity. For 8-bit outputs, rather than calculating the absolute velocity in scientific units, RVP900 calculates the mean velocity for the normalized Nyquist interval [-1,1], that is, the output � values are, �′...
Page 206: Spectrum Width Algorithms
To a lesser extent, the antenna rotation rate can also effect the spectrum width. At high elevation angles, the fall speed dispersion of the scatterers also effects spectrum width. There are two choices for the spectrum width algorithm used in the RVP900, depending on the speed and accuracy that are required for the application: •...
Page 207: Signal Quality Index (Sqi Threshold)
7.4.5.1 R0, R1 Width Algorithm (page 204). 7.4.6 Signal Quality Index (SQI threshold) Using the signal quality index (SQI), RVP900 can eliminate signals which are either too weak to be useful, or which have widths too large to justify further analysis. �...
Page 208: Weather Signal Power (Sig Threshold)
RVP900 User Guide M211322EN-J The algorithm for calculating CCOR depends on whether the optional R autocorrelation lag is computed. 7.4.7.1 R0, R1 Clutter Correction � In this case CCOR is estimated from, � + � �� = 10log = 10log = 10log ��...
Page 209: Signal+Noise) To Noise Ratio (Log Threshold)
�� = 10log � (when applied to the other parameter) 7.5 Thresholding 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 •...
Page 210: Table 55 Threshold Qualifiers
Identification is based on combined interpretation of polarimetric measurements of reflectivity, differential reflectivity, differential phase and co-polar correlation coefficient by the HydroClass pre-classifier. The following table shows the default threshold combinations for each of the parameters that can be selected for output from RVP900:...
Page 211: Adjusting Threshold Qualifiers
Chapter 7 – Processing Algorithms Table 56 Default Threshold Combinations Parameter Description Threshold Reflectivity with clutter correction LOG and CCOR Reflectivity without clutter correction Mean velocity SQI and CCOR SQI and CCOR and SIG Spectrum width Dual Pol Differential reflectivity 7.5.2 Adjusting Threshold Qualifiers When optimizing thresholds for your application, it is recommended that you change only one parameter (level or criterion) at a time so that you can verify the effect.
Page 212: Speckle Filter Processing
A speckle filter is a final pass over each output ray, in which isolated, single bins of velocity, width, or intensity are removed. There are two speckle removers in RVP900: • 1D single-ray speckle filter (default)—This is used for any output parameter.
Page 213: Figure 45 1D Speckle Filtering Algorithm
‣ Speckle Filter (page 44) 7.5.3.1 1D Speckle Filter A ray is the basic azimuth unit of RVP900 (for example, 1°) over which the samples are averaged to obtain the output base data (T, Z, V, W). For this filter, a speckle is defined as any single, valid bin (not thresholded), having thresholded bins on either side of it in range.
Page 214: Table 59 2D 3X3 Speckle Filter Rules
RVP900 User Guide M211322EN-J The filter examines 3 adjacent range bins from 3 successive rays to assign a value to the center point. For each output point, its 8 neighboring bins in range and time are available to the filter. Only the dBZ, dBT, Velocity, and Width data are candidates for this filtering step.
Page 215: Figure 46 2D 3X3 Filtering Concept Examples
Chapter 7 – Processing Algorithms Figure 46 2D 3x3 Filtering Concept Examples For all the parameters except velocity, the interpolated value for filling is computed as the arithmetic mean of all available neighbors. The procedure for velocity is similar, except that the 8-bit angles are first converted to Cartesian vectors, then averaged and converted back to polar.
Page 216: Reflectivity Calibration
RVP900 User Guide M211322EN-J 1. The most recent and the previous ray are used. For every valid point in the most recent ray, the algorithm performs a search among the three nearest neighbors in the previous ray to find a valid velocity. The search pattern is shown at the bottom of...
Page 217: Figure 47 Model Intensity Curve - Power At Antenna Feed (2Db Per Major Division)
, Let G represent the overall gain of the RF and IF components leading up to RVP900. The green line can be interpreted as the response of an ideal noise-free amplifier having gain GdB , while the red curve is the response of the real-world amplifier(s) whose equivalent front-end noise is I...
Page 218 In the above example, a 1.2 dB LOG detection threshold is shown (horizontal blue line) for the received signal. If RVP900 applies sufficient range and time averaging so that thermal noise alone produces very few false alarms above 1.2 dB, then P...
Page 219: Single-Point Direct Method For Calibration Of I O
Chapter 7 – Processing Algorithms 6. Correct the value for losses. 7.6.3 Treatment of Losses in Calibration (page 218). 7.6.2 Single-Point Direct Method for Calibration of I • Signal generator output calibrated in absolute dBm • Power meter for checking the signal generator calibration This calibration method uses the TTY setup commands.
Page 220: Treatment Of Losses In Calibration
RVP900 User Guide M211322EN-J 7.6.3 Treatment of Losses in Calibration When calibrating the dBm level of the test signal, you must account for any losses that may occur between the antenna feed and the injection point, and in the cable and coupler that connect the signal generator to the injection point.
Page 221: Determining Dbzo
Chapter 7 – Processing Algorithms �� = − 50 − 30 + 2 = − 82 �� If the test signal generator output is -50 dBm, the injected power is �� = − 82 + 3 = − 79 �� The equivalent power at the feed is then 3 dB more than this: ��...
Page 222: Dual Prt Processing Mode
RVP900 User Guide M211322EN-J If the value of I calculated above was not based on loss-corrected dBm values, correct I �� = �� − �� − �� + �� as follows: 0 �� : �� Example Calculation of dBZo Use this sample calculation to check your arithmetic.
Page 223: Dprt-1 Mode
PRF limit, which typically is much higher. You must make sure that the PWINFO command is disabled in the RVP900 Mcsetup menu. There is no duty cycle protection if you do not do this.
Page 224: Dprt-2 Mode
DPRT-2 algorithm is similar, except that the folded velocity from both PRTs are unfolded independently and then averaged together. In addition to the above, RVP900 computes the DC average of the (I,Q) data within each bin. This is used as a simple estimate of clutter power, so that corrected reflectivities are available in DPRT-2 mode when a non-zero clutter filter is selected.
Page 225 If the target is at all noisy, then this increase in variance can be severe. Rather than use Ø directly, the RVP900 uses it only as a rough estimate in determining how to unfold the individual velocity measured from each...
Page 226: Figure 49 Dual Prf Concepts
Region 1. The resultant angle is the same in each case. RVP900 makes efficient use of the incoming data by unfolding velocities from both the low and the high-PRF data, making use each time of information in the previous ray. When low- PRF data are taken the derived velocities are unfolded by combining information from the previous high-PRF interval.
Page 227 Although the RVP900 trigger generator can produce any trigger frequency, only the 3:2, 4:3, and 5:4 ratios can be used with the built-in unfolding algorithms. The RVP900 still permits other PRT ratios to be explored, but the unfolding technique must then be manually programmed on your host computer.
Page 228: Random Phase Second Trip Processing
2nd trip echoes can obscure valid first trip velocity information. RVP900 has optional random phase processing for the filtering and recovery of second trip echoes. While details of the technique are proprietary to Vaisala, we describe the general principle and the configuration options to optimize the algorithm performance.
Page 229: Random Phase Second Trip Processing Algorithm
COHO. Klystron Radars For a Klystron radar, the phase is controlled by RVP900 through a digital phase shifter that is precisely calibrated. Typically the Klystron COHO is phase shifted so that each transmit pulse has a different phase.
Page 230: Figure 51 Random Phase Processing Algorithm
RVP900 User Guide M211322EN-J Ideal 2nd Trip Ideal 1st Trip Raw 1st Trip with Raw 2nd Trip with 2nd Trip Noise Contamination 1st Trip Noise Contamination Filtered 2nd Trip Filtered 1st Trip Inverse Transfrom and Re-Cohere Recovered 1st Trip Recovered 2nd Trip Figure 51 Random Phase Processing Algorithm...
Page 231: Tuning For Optimal Performance
Since the strong echo generates noise that obscures the weaker 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 of the phase information for the other trip is then contained in the white noise portion of the spectrum.
Page 232 As an example, if RVP900 is operating in random phase mode at a PRF of 1500Hz, and is observing widespread weather having uniform intensity in both the first 100Km trip and the second 100Km trip.
Page 233: Signal Generator Algorithm Testing
227). 7.10 Signal Generator Algorithm Testing The IF signal generator tests that can be used to verify the RVP900 processing algorithms. Perform these tests after adding new algorithms or major modes to the processor. You can use the test descriptions to debug your system, or better understand how they work.
Page 234: Verifying Phidp And Kdp
We would thus observe a velocity of (0.8 × Vu) at 300 km, where Vu is the unambiguous Doppler velocity in meters/sec. Note that these phase difference calculations have made no assumptions about the RVP900 processing mode, and thus are valid in all major modes (PPP, FFT, DPRT, RPH), as well as in all Dual-PRF unfolding modes.
Page 235 If we now observe the two receive channels with the RVP900 at a PRF of 800Hz, we see the RHOAB terms varying with range; reaching a high value of 1.00, and a low value of 0.707.
Page 236 RVP900 User Guide M211322EN-J...
Page 237: Host Computer Commands
Output 1, Output 2, and so on. Often each word is broken down into independent fields, each consisting of one or more bits. All data transferred to or from RVP900 are in the form of 16-bit words. Unless otherwise noted, the command descriptions describe set bits.
Page 238: First-In-First-Out (Fifo) Buffer
When reading from the processor, the host can fall behind by as many as 4096 words before performance slows. RVP900 writes to the FIFO at full speed as long as it is not full. Internal processing is not affected by the exact speed at which user I/O occurs.
Page 239: Operation (Nop)
The discarded output data are not lost. The data are eventually replaced with an equal number of zeros. Each time RVP900 discards an output word, it increments an internal 24- bit count. When FIFO space becomes available, the processor replaces the missing data with zero-valued placeholders.
Page 240 33 bins would be output. This is because the 100- bit mask left a dangling 100th sample. In the extreme case where there are not enough mask bits to result in even one complete bin, the RVP900 forces the averaging to zero and turns on a single bin at zero range.
Page 241: Setup Operating Parameters (Soprm)
Chapter 8 – Host Computer Commands --------------------------------------------------------------- Bits for ranges 0.000kmto 1.875km Input 1 |--------------------------------------------------------------- \_1.875 \_0.000 --------------------------------------------------------------- Bits for ranges 1022.000 km to1023.875 km Input 512 |--------------------------------------------------------------- \_1023.875 \_1022.000 8.4 Setup Operating Parameters (SOPRM) Use SOPRM to configure the signal processor. You must issue SOPRM when any of the parameters in the list change.
Page 242: Table 62 Soprm Threshold Options
RVP900 User Guide M211322EN-J --------------------------------------------------------------- |ZNS| Polar |NHD |ASZ|16B|CMS|R2 | |3x3|CCB| |Lsr|Dsr|Rnv| Input 2 |--|---|-------|----|---|---|---|---|---|---|---|---|---|---|---|- Each single-bit field selects whether the given processing or threshold option is enabled (1) or disabled (0). Table 62 SOPRM Threshold Options Threshold Description Option If Rnv is 0 (no range normalization), you can set ZNS to have the dBZ and dBT outputs to be power relative to noise (P/N) rather than SNR ((PN)/N).
Page 243 7.5.3 Speckle Filter Processing (page 210). RVP900 automatically handles all of the pipelining overhead associated with running the 3×3 filter. Valid output data are always obtained in response to every PROC command. Circular autocorrelation bias correction. Setting this bit causes non-windowed spectra to produce autocorrelation terms that exactly match those that would be computed by traditional PPP sums, that is, with the spurious end-around term removed.
Page 244 Input 9 |--------------|---------------|--------------------------------| The TopMode bits select the overall data acquisition and processing mode for RVP900. Although the processing algorithms used in each top level mode are different, the RVP900 command set works in a uniform way in all modes.
Page 245: Table 63 Topmode Bits
Delay This delay is introduced prior to processing the next ray of data when Dual- PRF velocity unfolding is enabled or the RVP900 has been reconfigured by user commands. The delay permits the clutter filter transients to settle down following PRF and gain switches.
Page 246 • 3:Exact Blackman • 4:VonHann If set, RVP900 attempts to run its standard processing algorithms even when a custom trigger pattern has been selected with the SETPWF command. Unfold velocities using a simple (Vhigh Vlow ) algorithm, rather than the standard algorithm described in 7.5.3.2.1 Dual-PRF Unfolding (page 213)
Page 247: Table 65 Example Flag Values With Acceptance Criteria Combinations
Chapter 8 – Host Computer Commands Table 65 Example Flag Values With Acceptance Criteria Combinations Value Criteria FFFF All Pass (Thresholds disabled) 0000 All Fail (No data are passed) AAAA 8888 LOG and CSR A0A0 LOG and SQI 8080 LOG and CSR and SQI F0F0 FAFA SQI or LOG...
Page 248 RVP900 User Guide M211322EN-J --------------------------------------------------------------- Threshold Control Flags for Velocity Input 13 |---------------------------------------------------------------| See description for Input 11. --------------------------------------------------------------- Threshold Control Flags for Width Input 14 |---------------------------------------------------------------| See description for Input 11. --------------------------------------------------------------- Additive Offset for Measured AZ Angles (Binary Angle)
Page 249 Chapter 8 – Host Computer Commands else G = 0.1 + (N - 10000)/10000 This format is backward-compatible with the previous linear format for all values between 0.0 ... 0.1 dB/km and it extends the upper range of values from 0.65535 ... 5.6535. These larger attenuation corrections are needed for very short wavelength radars.
Page 250 RVP900 User Guide M211322EN-J --------------------------------------------------------------- Range smoothing (0:None, 1:pairs, etc) XARG 2 |---------------------------------------------------------------| Range smoothing can be performed on raw moment data prior to the computation of scientific parameters. The number of bins to sum together is given here. This should generally be an odd integer so that no range bias is introduced by the smoothing operation.
Page 251 This word is a combination of MMTS_xxx bits, defined in dsp.h, specifying what types of mismatches are okay (do not cause an all-zero ray to be produced) during PROC command processing of timeseries data that are played back from an external source into RVP900. ---------------------------------------------------------------...
Page 252: Interface Input/Output Test (Iotest)
RVP900 User Guide M211322EN-J Table 66 Default Values For Melting Height Operating Parameters Parameter Scientific Units Input Sample Size 25 pulses Flag Word 0007 Hex Log Slope 1966 0.03 dB/LSB LOG Threshold 0.5 dB CCOR Threshold 25.0 dB Signal Quality Index Threshold 0.5 (dimensionless)
Page 253: Interface Output Test (Otest)
Chapter 8 – Host Computer Commands --------------------------------------------------------------- Command |-------------------------------------------|-------------------| --------------------------------------------------------------- Arbitrary Data Word #1 Supplied by Host Controller | Input 1 |---------------------------------------------------------------| --------------------------------------------------------------- Arbitrary Data Word #16 Supplied by Host Controller | Input 16 |---------------------------------------------------------------| The IOTEST command can also process and echo up to 128 additional XARGS data words. 8.21 Pass Auxiliary Arguments to Opcodes (XARGS) (page 306).
Page 254: Sample Noise Level (Snoise)
Two bits in the command word determine which, if any, of the new values overrides the current values stored in RVP900. The power-up sampling range is 250 km (input value of 250), and the power-up trigger rate is 200 Hz (input value of 30000). These initial values persist until such time as they are altered here.
Page 255 Reissue the SNOISE command periodically to compensate for drift in the RF and A/D systems. The noise levels must be measured for the RVP900 to properly process data. This can be done by issuing the SNOISE at least once after power-up, or by setting the correct values for the power-up noise levels with the Mt setup command (see 5.2.6 Mt<n>...
Page 256 RVP900 User Guide M211322EN-J Do not compute a noise sample, but rather, restore the powerup noise defaults. --------------------------------------------------------------- Starting Range in km (Max 992km) of 32km Sampling Interval Input 1 |---------------------------------------------------------------| --------------------------------------------------------------- Internal Trigger Rate (6Mhz/N) to use During Noise Sampling...
Page 257: Initiate Processing (Proc)
Chapter 8 – Host Computer Commands --------------------------------------------------------------- <Spare> |Err|Ttf|Ntg| Input 6 |---------------------------------------------------|---|---|---| The following XARGS input words are optional, only if Action=1 and hybrid pulse. --------------------------------------------------------------- (MSB) Log of Measured Noise Level, puse 2 (LSB) XARG 1 |------|--------------------------------------------------------| --------------------------------------------------------------- NOISE Level Standard Deviation, pulse 2 (in 1/100 of a dB) XARG 2 |------|--------------------------------------------------------| ---------------------------------------------------------------...
Page 258: Table 67 Proc Modes
Optional Dual-PRF velocity unfolding is chosen by command bits 8 and 9. For Doppler data either a 2:3, 3:4, or 4:5 PRF unfolding ratio may be selected. RVP900 performs the unfolding steps internally, so mean velocity is output with respect to the larger unambiguous interval.
Page 259 Chapter 8 – Host Computer Commands For example, if TAG angle headers are requested, if the ARC, Z, and V bits are all set, and if there are 100 bins selected in the current range mask, then each RVP900 output ray consists of the following:...
Page 260: Table 68 Proc 8-Bit And 16-Bit Data Formats
SOPRM Command Input word #2 (see 8.4 Setup Operating Parameters (SOPRM) (page 239)). The same SOPRM word configures RVP900 for single or dual polarization. The latter is required for Kdp, PDP, and RHV to be computed properly. Table 68 PROC 8-bit and 16-bit Data Formats...
Page 261 Chapter 8 – Host Computer Commands Parameter Description 8-bit Format 16-bit Format Selects spectral Spectral width is computed from Spectral width in meters per � width data. the unsigned byte N as: second (m/s) is computed from � � �� the unsigned word N as: �...
Page 262 RVP900 User Guide M211322EN-J Parameter Description 8-bit Format 16-bit Format Selects differential The level in decibels is computed Same as 16-bit decibel format for �128 reflectivity data. from the unsigned byte N as: �� = The overall range is from -7.935 dB to +7.935 dB in 1\16 dB steps as...
Page 263 Chapter 8 – Host Computer Commands Parameter Description 8-bit Format 16-bit Format Selects dual The phase angle in degrees is The phase angle in degrees is polarization computed on a 180° interval from computed on a 360° interval from � − 1 �...
Page 264 RVP900 User Guide M211322EN-J Parameter Description 8-bit Format 16-bit Format Selects Linear The level in decibels is computed Same as 16-bit decibel format for Depolarization from the unsigned byte N as: Ratio, measured dB = -45.0 + (N-1) / 5...
Page 265 Chapter 8 – Host Computer Commands Parameter Description 8-bit Format 16-bit Format HCLASS Hydrometeor There are several possible classification schemes. The choice is made in Classification the dpolapp_*-band.conf file, where * is C (for C-band radars) (HydroClass) and S (for S-band radars). parameter.
Page 266: Table 69 Tsout Random Phase Major Mode Values
RVP900 User Guide M211322EN-J --------------------------------------------------------------- | TSOUT | Sub Type |Unfold | 1 | 0 1 |0 Command |---|---|----------------|-------|---|-------|-------------------| When the TSOUT bits select Power Spectrum then, depending on the current major mode, a further choice may be needed to select one of several spectral view points. The following table shows the values for the random phase major mode the possible values of Sub Type.
Page 267 Chapter 8 – Host Computer Commands --------------------------------------------------------------- Exponent | S | Mantissa |------------------|---|----------------------------------------| --------------------------------------------------------------- Log of Power in Sample (LOG) |--------------|------------------------------------------------| To convert these legacy format floating I and Q samples to voltages: 1. Create a 12-bit signed integer in which bits 0 ... 9 are copied from the Mantissa field, and bits 10 and 11 are either 01 or 10 depending on whether S is 0 or 1.
Page 268 Slope Log Power Slope word 3 of the SOPRAM command. 0.03 is recommended. For backwards compatibility, RVP900 produces a 8-bit fixed point time series format. Because of the limited dynamic range available, this only shows strong signals, and is not recommended for use.
Page 269 (BxN) is odd; followed by the first half of the V data, also in their normal order. Only the first halves of the individual H and V sample arrays are output by RVP900. As an example, if you select 25 bins and 100 pulses, then the output data consists of 1250 H samples (from all bins in the first 50 pulses), followed by 1250 V samples from the exact same set of bins and pulses.
Page 270: Load Clutter Filter Flags (Lfilt)
When the number of output words is large there is a possibility that the internal buffering within RVP900 may overflow and data may be lost. Due to internal memory limitations, the product (BxN) must be less than 12000. A bit in the latched status word indicates when time series overflows occur.
Page 271 This lets you specify a 2D or even 3D table of clutter filter selections that are dynamically selected during live data processing. RVP900 maintains an internal array of up to 1024 different filter- versus-range tables, each of which is keyed to a particular solid angle AZ/EL sector. Each enhanced LFILT command...
Page 272 RVP900 User Guide M211322EN-J --------------------------------------------------------------- Internal Slot for This Filter Ray Specification (0–1023) XARG 1 |----------------------------------------------------------------| --------------------------------------------------------------- Number of Bins of Filter Selections to Load (0–4200) XARG 2 |----------------------------------------------------------------| --------------------------------------------------------------- Lower AZ (Binary angle) XARG 3 |-------------------------------|--------------------------------| --------------------------------------------------------------- Upper AZ (Binary angle)
Page 273: Get Processor Parameters (Gparm)
|-------------------------------|--------------------------------| Total of Ceil(NBins/2) Words Loaded 8.10 Get Processor Parameters (GPARM) Use GPARM to access status information from the RVP900 processor. 64 words are always transferred. Some words are reserved for future compatibility and are read as zeros. Table 70 RVP900 Status Output Words...
Page 274 RVP900 User Guide M211322EN-J Word Description Noise Trigger Period Pulse Width 0 min. Trig. Period Pulse Width 1 min. Trig. Period Pulse Width 2 min. Trig. Period Pulse Width 3 min. Trig. Period Pulse Width Bit Patterns Current/Pulse Width Current Trigger Gen. Period Desired Trigger Gen.
Page 275 Output 1 |---------------|-----------|------------------------------------| Shows the revision and serial numbers of the RVP900 board. This information is useful when computer software is designed to handle many signal processor revisions. The revision number is 7 bits total, 4 of which are in the high four bits of the word for compatibility with an older format.
Page 276 RVP900 User Guide M211322EN-J --------------------------------------------------------------- TRIGIN Current Trigger Period in 1/8km (0.83333 usec) Steps Output 3 |----------------------------------------------------------------| --------------------------------------------------------------- Current Sample of TAG bits 15–0 Output 4 |-------------------------------|--------------------------------| --------------------------------------------------------------- Current Sample of TAG bits 31–16 Output 5 |----------------------------------------------------------------| --------------------------------------------------------------- 0 | (MSB)
Page 277 Chapter 8 – Host Computer Commands These two words convey the measured I and Q DC offsets from the last noise sample. The output format is either signed 16-bit values in which ±32767 represent ±1.0 (legacy format), or packed time series values using the High-SNR encoding format. Bit-9 of GPARM Word-59 shows which format to use.
Page 278 Bit 8 DSP has full IAGC hardware and firmware configuration Bit 9 DSP supports 16-bit floating time series Bit 11, 10 Current unfolding mode Bit 13, 12 Number of RVP900/PROC compute processes minus one Bit 14 DSP supports Power Spectrum output...
Page 279 Chapter 8 – Host Computer Commands --------------------------------------------------------------- Diagnostic Result Register A Output 11 |----------------------------------------------------------------| Bit 0 Error loading config/setup files Bit 1 Error attaching to antenna library Bit 2 Problem when forking compute processes Bit 3 Signals raised during startup Bit 4 RVP running without root privileges Bit 5...
Page 280 Trigger Count (high 8-bits) Output 15 |----------------------------------------------------------------| The trigger count is a running tally of the number of triggers received by the RVP900 on the TRIGIN line. It is a full 24-bit counter. --------------------------------------------------------------- | Number of Properly Acquired Bins for Current Range Mask & PRT...
Page 281 IFDR test switches are not in their normal operating position Bit 12 Set according to whether the RVP900 is performing trigger blanking. This allows the host computer to decide whether to interpret the End-TAG-0 bit in the output ray header as a blanking flag, or as a normal TAG line.
Page 282 RVP900 User Guide M211322EN-J --------------------------------------------------------------- Min Trig Period (0.16667usec Increments) for Pulse Width 0 Output 21 |----------------------------------------------------------------| --------------------------------------------------------------- Min Trig Period (0.16667usec Increments) for Pulse Width 1 Output 22 |----------------------------------------------------------------| --------------------------------------------------------------- Min Trig Period (0.16667usec Increments) for Pulse Width 2...
Page 283 Chapter 8 – Host Computer Commands TopMode Major Mode. See Input #9 in 8.4 Setup Operating Parameters (SOPRM) (page 239). Window Spectral Window Choice. See Input #10 in 8.4 Setup Operating Parameters (SOPRM) (page 239). PWidthS Pulse width of second pulse in hybrid transmit waveform Bit indicating second pulse in use in hybrid transmit waveform --------------------------------------------------------------- Current Trigger Generator Period (0.16667usec Increments)
Page 284 RVP900 User Guide M211322EN-J The PRTs from the start and end of the last ray are the measured values when possible, that is, when non-simulated data are being processed, and we either have an external trigger, or an internal trigger that is not in any of the dual-PRT modes. The units are the same as for the measured current trigger period in Output #3.
Page 285 Chapter 8 – Host Computer Commands --------------------------------------------------------------- SIG Threshold in 1/16 of dB Output 36 |----------------------------------------------------------------| (From V) --------------------------------------------------------------- Calibration Reflectivity in 1/16 of dB Output 37 |----------------------------------------------------------------| --------------------------------------------------------------- Reserved (Zero) Output 38 |-------------------------------|--------------------------------| --------------------------------------------------------------- Reserved (Zero) Output 39 |-------------------------------|--------------------------------| --------------------------------------------------------------- | Range Avg (From LRMSK Command) | Output 40...
Page 286 RVP900 User Guide M211322EN-J --------------------------------------------------------------- Reserved (Zero) Output 42 |-------------------------------|--------------------------------| --------------------------------------------------------------- Header Config of PROC data (CFGHDR Input #1) Output 43 |----------------------------------------------------------------| --------------------------------------------------------------- Noise Sum of I Squared =2**–16LSB=2**–31 Output 44 |----------------------------------------------------------------| --------------------------------------------------------------- Noise Sum of I Squared MSB=1LSB=2**–15 Output 45...
Page 287 Previously, these words helped balance the individual gain of the I and Q channels in RVP6 in the presence of a strong test signal. Since I and Q are inherently balanced in the RVP900, these output words are no longer of much value. ---------------------------------------------------------------...
Page 288 7.2.5 Interference Filter (page 178). MinRev Minor revision level of the RVP900 code that is currently running IFDR Sat.Power Input power required to saturate the IF-Input A/D converter for the IFDR that is currently attached • 0: +4.5 dBm •...
Page 289 Chapter 8 – Host Computer Commands Bit 5 Processor supports DPRT-2 (dual-PRT) algorithms Bit 6 Could not generate the requested phase sequence Bit 7 Unused Bits 8-11 User-defined Major Modes 1 ... 4 are supported --------------------------------------------------------------- Signed trigger slew in hundredths of microseconds Output 56 |----------------------------------------------------------------| This is the same format that is used by the SETSLEW command to set the current trigger...
Page 290 Using High-SNR packed (I,Q) format Bit 5 Trigger sequence truncated due to insufficient pattern memory Bit 6 Time series data source is external to RVP900 Bit 7 WSR88D Batch mode is supported Bit 8 Major mode refuses to use external trigger...
Page 291: Load Simulated Time Series Data (Lsimul)
A/D converters as is ordinarily the case. Since the properties of the simulated data are known exactly, it is possible to verify that the calculations within the RVP900 are proceeding correctly.
Page 292 (I,Q) data. You may specify one or more bins to be loaded, and RVP900 replicates these data as necessary in order to fill out the entire count of acquired bins. If the number of bins is 0, then a zero-valued sample is applied for all channels.
Page 293 Chapter 8 – Host Computer Commands In the legacy format #2 (RVP5-RVP900) each bin within the pulse is represented by four 16- bit fixed point words. The total number of words loaded is (4+4B), where B is the bin count specified in Word #1.
Page 294: Reset (Reset)
| S | Mantissa Input 6 (Q) |-------------------|---|----------------------------------------| 8.12 Reset (RESET) The RESET command permits resetting either the entire RVP900 processor, or selected portions. Flags in the command word determine the action to be taken. --------------------------------------------------------------- |Nv |Nse|Fif |Nv |Nv | 0 Command |-----------------------|---|---|----|---|---|-------------------| Reloads configuration from the saved nonvolatile settings.
Page 295: Define Trigger Generator Waveforms (Trigwf)
(TRIGWF) Do not use TRIGWF in any new code applications that drive RVP900. CAUTION! Use the interactive trigger setup procedure to define RVP900 triggers and timing. See 6.5 Pb — Plot Burst Pulse Timing (page 132). TRIGWF is obsolete . It is included for backward compatibility with RVP6. The code is disabled by default.
Page 296: Define Pulse Width Control And Prt Limits (Pwinfo)
0 ... 3, 01 loads codes 4 ... 7, and so on. RVP900 drives four TTL output lines (PWBW0 – 3) which control the radar pulse/ bandwidth hardware. Typically this control is through relays or solid-state switches in the transmitter and receiver.
Page 297 The PWINFO command can be disabled (for transmitter safety), so that PRT limits cannot accidentally be changed by the host computer. When this is done RVP900 still reads the five input words, but no changes are made to the pulse width and PRT information. The command I/O behaves the same way, whether enabled or disabled.
Page 298: Set Pulse Width And Prf (Setpwf)
RVP900 User Guide M211322EN-J --------------------------------------------------------------- Min Trig Period (0.16667usec Increments) for Pulse Width 1 Input 3 |----------------------------------------------------------------| --------------------------------------------------------------- Min Trig Period (0.16667usec Increments) for Pulse Width 2 Input 4 |----------------------------------------------------------------| --------------------------------------------------------------- Min Trig Period (0.16667usec Increments) for Pulse Width 3...
Page 299: Load Antenna Synchronization Table (Lsync)
8.16 Load Antenna Synchronization 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 does not need to separately monitor the antenna angles and request each data ray individually.
Page 300 – the antenna only needs to move across them. This minimizes the possibility of losing data due to missing codes in the angle encoders. RVP900 automatically produces an output ray after one second of waiting, even if no trigger angles have been crossed.
Page 301: Figure
1. Use the LSYNC command to load 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 pass 0°...
Page 302: Set Or Clear User Led (Sled)
Each ray begins immediately upon the user's request, or upon completion of the previous ray when in continuous processing mode. b. At the start of the ray, RVP900 finds the pair of sync angles that enclose the previous trigger angle.
Page 303 |---------------|---|---|---|---|------------|--------------------| The operation codes are as follows: Sends the ASCII character in the upper byte of the word to the RVP900 as if it had been typed on the setup TTY keyboard. Allow scope plotting data to be output when a plot is being drawn. All relevant status and data words are output once upon each receipt of this command.
Page 304 RVP900 User Guide M211322EN-J The 2-bit intensities of each of 16 possible strokes of data is given in the following 4-word sequence. An intensity of 0 represents OFF; 1, 2, and 3 are successively brighter. --------------------------------------------------------------- 1 | 0 0 | Int 3...
Page 305: Load Custom Range Normalization (Ldrnv)
10[{{N-1}<devide>50}- 2], and the default correction table (automatically used on power-up) is 40(N - 101). The table values are stored and interpolated when RVP900 loads a new range mask. Custom values for the user ranges are then computed. See 8.3 Load Range Mask (LRMSK) (page 237).
Page 306: Read Back Internal Tables And Parameters (Rback)
Input 251 |----------------------------------------------------------------| 8.20 Read Back Internal Tables and Parameters (RBACK) 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. --------------------------------------------------------------- Data to Show...
Page 307 Chapter 8 – Host Computer Commands Data Number Description Ray history array consisting of six words per ray for the last 40 rays (in reverse time order) that were processed. Each six- word group holds: • Number of samples that went into the ray •...
Page 308: Pass Auxiliary Arguments To Opcodes (Xargs)
Opcodes (XARGS) XARGS provides a backward compatible mechanism for supplying additional (optional) arguments to other opcodes. The command may be used freely in the RVP900 instruction stream, even if the opcode being modified does not expect any optional arguments. XARGS is a NOP in that case.
Page 309: Load Clutter Filter Specifications (Lfspecs)
8.22 Load Clutter Filter Specifications (LFSPECS) RVP900 allows 7 different clutter filters (plus the fixed all-pass filter) to be resident at once, so that an appropriate filter can be selected 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.
Page 310: Configure Ray Header Words (Cfghdr)
Type:3 SPFILT_GMAP Gaussian Model Adaptive Processing Spectral Filter This is the RVP900 most advanced clutter filter, combining the best techniques for determining the clutter gap width and restoring whatever low-velocity spectral points are removed.
Page 311 TAG3116 End of Ray • When RVP900 operates in dual PRF mode, bit zero of the start TAG word is replaced 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 normal (1).
Page 312: Configure Interference Filter (Cfgintf)
(18 words total). 8.24 Configure Interference Filter (CFGINTF) RVP900 can optionally apply an interference filter to its incoming (I,Q) data stream, with the goal of rejecting occasional and sparse interference from other (usually man-made) signal sources.
Page 313: Set Afc Level (Setafc)
5.2.1 Mb — Burst Pulse and AFC (page 93). RVP900 automatically converts the new level to the configured analog or digital AFC output format. The exception is for the Motor/Integrator type of AFC loop, for which this command does nothing.
Page 314: Set Trigger Timing Slew (Setslew)
RVP900 User Guide M211322EN-J --------------------------------------------------------------- Command |---------------|------------------------------------------------| --------------------------------------------------------------- 16–Bit AFC/MFC Value (–32768 through +32767) Input 1 |-------------------|--------------------------------------------| 8.26 Set Trigger Timing Slew (SETSLEW) The Mt menu allows you to select a subset of triggers that can be slewed left and right to place the burst pulse accurately at range zero.
Page 315: Configure Phase Modulation (Cfgphz)
Chapter 8 – Host Computer Commands Depending on how the hunting process has been configured in the Mb menu, the procedure may take several seconds to complete. The RVP900 host computer interface remains functional during this time, but any acquired data is questionable.
Page 316: Set User Iq Bits (Uiqbits)
8.29 Set User IQ Bits (UIQBITS) UIQBITS loads user-specified bits that are included with the pulse headers in the RVP900 TimeSeries API data stream. The permanent Set/Clr bits are updated in the signal processor and retain their value from the last time they were defined.
Page 317: Set Individual Thresholds (Thresh)
Chapter 8 – Host Computer Commands --------------------------------------------------------------- Command |---------------|------------------------------------------------| --------------------------------------------------------------- 64 Permanent User Bits to SET Inputs 1–4 |----------------------------------------------------------------| --------------------------------------------------------------- 64 Permanent User Bits to CLEAR Inputs 5–8 |----------------------------------------------------------------| --------------------------------------------------------------- 64 Permanent User Bits to ONCE Inputs 9– |----------------------------------------------------------------| 8.30 Set Individual Thresholds (THRESH) The SOPRM command allows you to configure 4 threshold numbers used by all data types, and to select the threshold control flags for 5 of the data types.
Page 318 RVP900 User Guide M211322EN-J --------------------------------------------------------------- Command |---------------|------------------------------------------------| The first 3 words supply a mask that indicates which data types are being set: --------------------------------------------------------------- | Z | T | V | W |ZDR| |KDP | Input 1 |---|---|---|---|---|---|-------|----|---------------------------| --------------------------------------------------------------- |Flg|Phi Rho...
Page 319: Set Task Identification Information (Taskid)
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 associated with these data, and is available in the pulse information structures (struct rvp900PulseInfo) that are read from the Timeseries API.
Page 320 RVP900 User Guide M211322EN-J The TASKID command defines a 16-character Null-terminated name, along with a 16-bit sweep number and 16-bit auxiliary (user defined) number. You may use all 16 characters of the name, as it is stored internally in 17 slots.
Page 321: Define Prf Pie Slices (Prfsect)
Chapter 8 – Host Computer Commands 8.32 Define PRF Pie Slices (PRFSECT) This command supplements the SETPWF command and allows an alternate trigger PRF to be generated within prescribed AZ/EL sectors. See 8.15 Set Pulse Width and PRF (SETPWF) (page 296). Up to 8 trigger sectors can be defined by invoking PRFSECT for each separate region.
Page 322 RVP900 User Guide M211322EN-J --------------------------------------------------------------- Lower AZ (Binary angle) Input 2 |----------------------------------------------------------------| --------------------------------------------------------------- Upper AZ (Binary angle) Input 3 |----------------------------------------------------------------| --------------------------------------------------------------- Lower EL (Binary angle) Input 4 |----------------------------------------------------------------| --------------------------------------------------------------- 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.
Page 323: Configure Target Simulator (Targsim)
8.33 Configure Target Simulator (TARGSIM) RVP900 contains a built-in target simulator tool that can test and debug processing algorithms that work with multiple trip returns. Several real physical targets can be simulated, each having a range span measured in kilometers, a Doppler shift in Hertz, and an echo power relative to the saturation level of the receiver.
Page 324 RVP900 User Guide M211322EN-J --------------------------------------------------------------- Target Length in Tenths of Kilometers Input 3 |----------------------------------------------------------------| --------------------------------------------------------------- Target Power in Tenths of dB Relative to Saturation (signed) | Input 4 |----------------------------------------------------------------| --------------------------------------------------------------- Target Power Delta over Range Span in Tenths of dB (signed)
Page 325: Set Burst Pulse Processing Options (Bpopts)
Input 1 |---------------|------------------------------------------------| PLY/N Affects whether RVP900 phase locks its (I,Q) data to the measured burst pulse. The PLY and PLN bits force Yes and No responses. If both bits are clear or both bits are set, no change is made.
Page 326: Load Melting Layer Specification (Mlspec)
RVP900 can use spatially variable melting layer (ML) altitudes, which may be preloaded for each interval of data processing (PROC). The ML altitudes are referenced to the Mean Sea Level (MSL), and estimate the top of ML.
Page 327 This way, the melting layer height can be used in different live data processing applications such as HydroClass. RVP900 maintains an internal array of up to 1024 different filter versus- range tables, each of which is keyed to a particular angle (EL, for PPIs and AZ for RHIs). Each XOP_MLSPEC command uploads the complete sweep.
Page 328 RVP900 User Guide M211322EN-J --------------------------------------------------------------- Number of bins (Unsigned 16-bit integer) XARG 4 |----------------------------------------------------------------| --------------------------------------------------------------- Angular resolution (Unsigned 16-bit integer) XARG 5 |----------------------------------------------------------------| --------------------------------------------------------------- Bin staring in m (Unsigned 16-bit integer) XARG 6 |----------------------------------------------------------------| --------------------------------------------------------------- Bin spacing in cm (Unsigned 16-bit integer)
Page 329 Chapter 8 – Host Computer Commands Number of sweeps The minimum between the number of sweep of the running task and the DPOLAPP_MAX_ML_SWEEPS. 360000 The number of rays is calculated as #�� = Number of rays �� where iRES is the desired angular resolution expressed as an integer number of thousands of degrees.
Page 330 RVP900 User Guide M211322EN-J --------------------------------------------------------------- Melting layer altitude #1 Melting layer altitude #2 Input 3 |-------------------------------|--------------------------------| Number of Mlbins/2...
Page 331: Technical Data
Processing modes PPP, FFT/DFT, Random Phase 2nd trip filtering/recovery Range resolution N*15 m Range dealiasing by random phase 9.2 RVP900 Processing Algorithms Table 73 Processing Algorithms Algorithm Description I/Q signal correction options • Amplitude jitter correction based on running average of transmit power from burst pulse •...
Page 332: Rvp900 Input And Output Summary
Function Description AZ/EL angle input options • Serial AZ/EL angle tag input using standard Vaisala RCP format • 16-bit each parallel TTL binary angles through the I/O-62 card • Synchro angle inputs through the I/O-62 card • RCP network antenna packet protocol Ethernet I/O from host Data output of calibrated dBZ, V, and W during normal operation.
Page 333: Rvp901 Ifdr Specifications
Chapter 9 – Technical Data Function Description Optional Polarization Control RS-422 differential control for polarization switch Trigger Output Up to 12 total triggers available on various connector pins. Triggers are programmable with respect to trigger start, trigger width, and sense (normal or inverted). 9.4 RVP901 IFDR Specifications Table 75 IF Band Pass Filter Function...
Page 334: Table 77 Phase Stability
RVP900 User Guide M211322EN-J Characteristic Description Sampling rate 50 ... 100 MHz Saturation level +8.0 dBm @ 50 Ω Optional single and dual >120 dB polarization wide dynamic range Table 77 Phase Stability Characteristic Description Klystron Better than 0.1° Magnetron (for 1.0 microsecond Better than 0.5°...
Page 335: Rvp901 Digital Waveform Synthesis
Chapter 9 – Technical Data Table 80 RVP901 IFDR Physical Specifications Characteristic Description Dimensions 26.8 cm x 17.6 cm x 4.8 cm (10.5 in x 6.9 in x 1.9 in) Input power Available for 100 ... 240 VAC at 47 ... 63 Hz or 18 ... 6 VDC. •...
Page 336: Rvp902 Signal Processing Computer Specifications
RVP900 User Guide M211322EN-J Function Description TxDAC Analog Output • Two independent, digitally synthesized, analog output waveforms (SMA). Waveform Characteristics These outputs are electrically identical and logically independent IF waveform synthesizers that can produce phase modulated CW signals, finite duration pulses, compressed pulses, and so on.
Page 337: Rvp902 Safety Compliance
Chapter 9 – Technical Data Characteristic Description Non-operating environment Temperature: -40 ... 70° C (-40 ... 156° F) Humidity: 10 ... 95% @ 60° C, non-condensing Vibration (5 ... 500Hz): 2 G Operating environment Temperature: 0 ... 40° C (32 ... 122° F) Humidity: 10 ...
Page 338: Rvp900 Spare Parts
RVP900 User Guide M211322EN-J 9.8 RVP900 Spare Parts Table 84 RVP900 Spare Parts Part Number Description 223326SP AC Supply Assembly Spare part RVP900 DRW229161SP DC FAN DRW228541SP DC Power Cable with fans DRW229805SP DC Power Cable without fans RCP8-CPSP IO62 Panel RCP8...
Page 339: Type Plate
Chapter 9 – Technical Data Characteristic Description Input power RVP901 IFDR: • 100 VAC ... 240 VAC • 50 Hz ... 60 Hz auto-ranging ±5% RVP902 Main Chassis: • 100 VAC ... 240 VAC • 50 Hz ... 60 Hz auto-ranging Power consumption •...
Page 340: Figure 53 Rvp902-Io Type Plate
RVP900 User Guide M211322EN-J Figure 53 RVP902-IO Type Plate Part name Product code Voltage, current, and frequency Place of manufacture Serial number in bar code...
Page 341: Appendix A: Installation And Test Procedures
A supplementary test sheet is at the end of the test procedure. When you have successfully completed the installation and test procedures, your RVP900 is ready to connect to your software application, such as the Vaisala IRIS system. Perform the additional configuration and calibration procedures before using the RVP900 with the software.
Page 342: Test Checklist
RVP900 User Guide M211322EN-J A.2 Test Checklist Complete the installation checklist after installing the RVP. Record all values when instructed. Save the values for future reference. Table 87 RVP Test Checklist Task Checked OK/Not Remarks A.3 Installation Check (page 341) A.4 Power Up Check (page 342) A.5.1 Checking Terminal Setup (page 344)
Page 343: Installation Check
Date: A.3 Installation Check Test Goal Verify that the RVP900 is properly connected to the radar system and document some basic radar characteristics. There are differences for TWT/Klystron and magnetron radar systems. Checklist Record all values when instructed. Save the values for future reference.
Page 344: Power Up Check
RVP900 User Guide M211322EN-J Task Checked OK/Not Remarks Klystron Systems IF COHO is connected to J13 ADC–E of RVP901. Tx license key is installed (circle one): • Yes • No Test Passed For Customer Date: For Vaisala Date: A.4 Power Up Check Test Goal Verify that RVP901 and RVP902 properly power up.
Page 345: Terminal Setup Check
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 Procedure in A.5.1 Checking Terminal Setup (page 344) completed successfully. Test Passed For Customer Date: For Vaisala Date:...
Page 346: Checking Terminal Setup
2. To view RVP and IRIS software versions, type V 3. For a list 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.
Page 347: Checking Board Configuration With Setup Mc Command
5.1.2 V and Vz – View Card and System Status (page 89). Test Passed For Customer 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 application.
Page 348: Checking Processing Options With Setup Mp Command
RVP900 User Guide M211322EN-J Task Checked OK/Not OK Remarks Status information is correct and shows no faults. 5.2.2 Mc — Top-level Configuration (page 102). Parameters have been set. Test Passed For Customer Date: For Vaisala Date: A.8 Checking Processing Options with...
Page 349: Checking Clutter Filters With Setup Mf Command
5.2.3 Mf — Clutter Filters (page 104). Test Passed For Customer Date: For Vaisala Date: A.10 Checking General Trigger Setup with Setup Mt Command Test Goal Verify that the TTY setups for the General Trigger Setup section are properly configured for...
Page 350 M211322EN-J Background RVP900 can output up to 12 triggers. These can be delayed by different amounts, and have different pulse widths. For example, trigger 0 may go to fire the transmitter, while a slightly delayed trigger 1 may be used for triggering an oscilloscope. The timing can be different for each transmitter pulse width.
Page 351: Initial Setup Of Information For Each Pulse Width
The duty cycle limits of your radar should be obtained from your system documentation or radar manufacturer. RVP900 supports up to four pulse widths (coded 0 to 3), although most transmitters typically support only 2 pulse widths. Record, in the chart below, the pulse width in microseconds and the maximum PRF that is allowed for each pulse width.
Page 352: Checking Burst Pulse And Afc With Setup Mb Command
RVP900 User Guide M211322EN-J Pulse Width Max PRF ____ μsec ____ Hz Test Procedure 1. Enter the TTY setups through dspx. 2. Issue the Mt # command, once for each pulse width. 3. Enter the start time and widths for each trigger as shown in 5.2.6 Mt<n>...
Page 353: Checking Debug Options With The M+ Command
Appendix A – Installation and Test Procedures An external AFC can be used instead of RVP900 AFC, but it is not recommended. Background: Klystron or TWT-based Systems The COHO is measured instead of the burst pulse. Klystron systems that use a phase shifter should input the phase shifted COHO into the IFD, so that RVP900 can digitally lock to the transmitted phase.
Page 354: Checking Transmitter Phase Control With Setup Mz Command
Background RVP900 supports several test features that are configured in this section. Vaisala recommends that the LEDs be set to 1:Go/Proc so that the front panel red LED flashes during each processing cycle. For operational systems, turn off the simulation feature.
Page 355: Ascope Test
Parameters are set. 5.2.7 Mz — Transmissions and Modulations (page 126). Test Passed For Customer Date: For Vaisala Date: 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.
Page 356: Burst Pulse Alignment
RVP900 User Guide M211322EN-J Checklist Table 100 Ascope Setup Checklist Task Checked OK/Not OK Remarks Test procedure completed successfully. Parameters are set. See TTY nonvolatile setups in IRIS and RDA Utilities Guide. Test Passed For Customer Date: For Vaisala Date: A.16 Burst Pulse Alignment Test Goal Verify that the burst pulse is present and that its amplitude is sufficient.
Page 357: Bandwidth Filter Adjustment
Parameters are set. 6.5 Pb — Plot Burst Pulse Timing (page 132). Parameters have been set. Test Passed For Customer Date: For Vaisala Date: A.17 Bandwidth Filter Adjustment Test Goal Set the band width filter for each pulse width. Test Equipment KVM connected...
Page 358: Digital Afc (Dafc) Alignment (Optional)
Parameters are set. 6.6 Ps — Plot Burst Spectra and AFC (page 137). Test Passed For Customer Date: For Vaisala Date: A.18 Digital AFC (DAFC) Alignment (Optional) Test Goal Verify that RVP900 DAFC output controls the STALO over the correct span.
Page 359: Table 103 Dafc Setup Checklist
Appendix A – Installation and Test Procedures Background RVP900 implements an AFC based on the measurement of the burst pulse frequency. The DAFC connects to the TRIG–A sma port of RVP901. It translates the AFC requests from the RVP900 main chassis into digital output requests supporting up to 25 bits. A frequency control span of approximately ±7 MHz is expected.
Page 360: Mfc Functional Test And Tuning (Optional)
A.19 MFC Functional Test and Tuning (Optional) Test Goal Verify that the Manual Frequency Control (MFC) is functioning properly. Skip this test if you are not using the RVP900 AFC. Test Equipment KVM connected Test Procedure 1. Enter the TTY setups through dspx.
Page 361: Afc Functional Test (Optional)
Parameters are set. 6.6 Ps — Plot Burst Spectra and AFC (page 137). Test Passed For Customer Date: For Vaisala Date: A.20 AFC Functional Test (Optional) Test Goal Verify that the AFC properly tracks the burst pulse frequency. Test Equipment KVM connected Test Procedure 1.
Page 362: Checking Input If Signal Level
RVP900 User Guide M211322EN-J 3. Verify the following: • Verify the system is in AFC mode by checking that the text on the terminal for the AFC % output says • Verify the frequency displayed on the setup terminal is within ±15 KHz of the center IF frequency (the default value for the AFC hysteresis outer limit in the Mb command);...
Page 363: Table 106 Input If Signal Level Setup Checklist
This verifies that the dominant noise comes from the LNA, and not from any of the subsequent IF amplifiers. Checklist Table 106 Input IF Signal Level Setup Checklist Task Checked OK/Not OK Remarks Test procedure completed successfully. Parameters are set. 6.7 Pr — Plot Receiver Waveforms (page 155). Test Passed For Customer Date: For Vaisala Date:...
Page 364: Checking Calibration And Dynamic Range
4. Use the setup terminal to enter the calibration gains, losses, and transmit power values. 5. Enter the TTY setups through dspx. 6. Use the ps command in the dspx utility to put RVP900 in manual AFC control by pressing = .
Page 365: Checking Receiver Bandwidth
Check that the signal generator frequency has not drifted by looking at the plot. h. If it is off by more than 0.1 MHz, retune and repeat the test. 12. In the dspx utility, put RVP900 back in automatic AFC control by typing the ps command and pressing =.
Page 366: Figure 54 Total Power And If Frequency
RVP900 User Guide M211322EN-J Test Equipment KVM connected RF signal generator Test Procedure 1. Connect the test signal generator to inject a signal at RF ahead of the LNA. 2. Enter the TTY setups through dspx. 3. Enter the Pr mode and make the following settings: •...
Page 367: Checking Receiver Phase Noise
Parameters are set. 6.7 Pr — Plot Receiver Waveforms (page 155). Test Passed For Customer Date: For Vaisala Date: A.24 Checking Receiver Phase Noise Test Goal Verify the stability of the STALO by looking at the phase noise of a clutter target. Background...
Page 368: Hardcopy And Backup Of Final Setups
RVP900 User Guide M211322EN-J 6. Record the Az, El, Range and Phase Noise: Az: ______ El:______ Range: ______ Phase Noise:______ Az: ______ El:______ Range: ______ Phase Noise:______ Az: ______ El:______ Range: ______ Phase Noise:______ Az: ______ El:______ Range: ______ Phase Noise:______...
Page 369: Rvp901 Txdac Stand-Alone Bench Test
4. Print the file or ftp it to a computer that supports a printer. /usr/sigmet/config Hardcopy Listings 1. Print the following files or ftp them to a computer that supports printing: • setup_dsp.conf • rvp900.conf • softplane_dsp.conf Backup /usr/sigmet/config directory Checklist Table 110 Backup and Hardcopy Checklist...
Page 370: Table 111 Rvp901 Txdac Stand-Alone Bench Test Checklist
RVP900 User Guide M211322EN-J 4. Enter the Pr menu and type RRRTTZ to move the starting plot range to 30 km, the plot interval to 20 μsec, and zoom factor to x2. 5. Type 2 space characters to switch to the spectral display plot and exit the plot by typing: q 6.
Page 371: Appendix B: Rvp901 Ifdr Technical Drawings
Appendix B – RVP901 IFDR Technical Drawings Appendix B. RVP901 IFDR Technical Drawings Figure 55 RVP901 IFDR - Top and Front Face...
Page 372: Figure 56 Rvp901 Ifdr - Right And Left Sides
RVP900 User Guide M211322EN-J Figure 56 RVP901 IFDR - Right and Left Sides Figure 57 RVP901 IFDR - Fan Side (Heat Sink) More Information ‣ RVP901 IF Digital Receiver (page 21)
Page 373: Appendix C: Rvp900 Developer Notes
IFDR, which samples the data. Using public APIs, researchers and OEM manufacturers can modify or replace existing algorithms, or write their own software using the RVP900 software as a foundation. RVP software runs under standard CentOS Linux, and is developed and maintained using standard GNU tools (for example, gcc, gdb, make).
Page 374 RVP900 User Guide M211322EN-J Component Description Linux Kernel Module This module is insmod at system boot time, provides all of the low-level PCI support for RVP hardware (Rx receiver card, Tx transmitter card, I/O-62 card, and so on.) It also provides the FIFO interfaces to the IRIS DSP driver and other services implemented at the kernel level.
Page 375: Rvp Software Maintenance Model
Figure 58 RVP Hardware and Software Organization C.2.1 RVP Software Maintenance Model In the Vaisala open source 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...
Page 376: Building A Customised Rda Tree
Description OPEN Fully populated with the source files used by Vaisala to build each RVP release. Use the OPEN code as a reference for programming examples and ideas. Note that OPEN code can change significantly with each release. Changes may be lost when you install the next RDA update.
Page 377: Showing Live Acquired Pulse Information: -Showaq
Appendix C – RVP900 Developer Notes Opcode 0x0004 (OTEST) Output Words0:0001 0002 0004 0008 0010 0020 0040 0080 0100 0200 0400 0800 10002000 4000 8000 Opcode 0x0005 (SNOISE) Input Words 0:0000 0000 Opcode 0x0009 (GPARM) Output Words 0:2000 0064 0960 9DCF 0110 0DD0 0000 0000 0000 5284 0000 0000 0040...
Page 378: Showing Coherent Processing Intervals: -Showcpis
RVP900 User Guide M211322EN-J PRT column Pulse repletion time for the last and the next pulses. Az and El columns Azimuth and elevation reported by the IFDR. iMisc column You may ignore this information. UDP:1 Frags:8150/8150/120 Bins:4086/0 PRT:324000/324000 iMisc:3e945c85 Az:178.32 El:148.05...
Page 379: Showing Realtime Callback Timers: -Showrtctrl
Appendix C – RVP900 Developer Notes You can monitor how the timeseries data stream is being organized into rays, by supplying the -showCPIs flag on the RVP startup command line. Here is a sample printout (while running Ascope): CPI0: 64–Pulses (269.74,1.49) to (271.25,1.49) 126.00–ms TS:1% CPI1: 64–Pulses (270.51,1.49) to (272.02,1.49) 126.00–ms...
Page 380 RVP900 User Guide M211322EN-J RTC –First- #0 ( dV:0 F:0 Rq:100000 ) #1(-) #2(-) RTC Setting timer #0 clock source to 0 (1MHz) RTC 0.100068 #0 ( dV:100009 F:1 Rq:2500 ) #1( dV:0 F:0 Rq :5 ) #2(-) RTC Setting timer #1 clock source to 1 (Trig) RTC 0.002512 #0 ( dV:2513 F:1 Rq:2500 ) #1( dV:2 F:0 Rq :5 ) #2(-)
Page 381: Using Ddd On Main And Proc Code
Appendix C – RVP900 Developer Notes C.3.5 Using ddd on Main and Proc Code The GNU ddd symbolic debugger is (usually) built on top of the dde command line debugger. Both tools are provided on all Linux systems. 1. To debug RVP9/Main code: a.
Page 382: Finding Memory Leaks With Valgrind
RVP900 User Guide M211322EN-J 2. To debug RVP9/Proc code, in an X-Term window type: $ rvp9 –noFork which starts RVP9/Main threads, but pauses at the point that the RVP9/Proc process would normally be created. The -noFork forces the subprocess count to one, as if you had included -procs 1 on the original command line.
Page 383: Profiling With Gprof
Appendix C – RVP900 Developer Notes The most common problem that it solves is finding reads-before-writes, that is, when you forget to set a value in a structure somewhere, and then reference it later before writing into it. Malloc/Free inconsistencies are also easily diagnosed with valgrind.
Page 384: Creating New Major Modes From Old Ones
You can code your own custom algorithms by making incremental changes to one of the Vaisala models, or you can start from scratch and build something unique. The best way to create a custom major mode is usually to start with the code for an existing one and incrementally modify it to include the new features.
Page 385: Function Pointers For Customization
Appendix C – RVP900 Developer Notes C.4.1 Function Pointers for Customization Each major mode is characterized by a set of function pointers or methods, which define how certain critical operations are to be carried out. The main RVP threads are governed by the following methods:...
Page 386: Real-Time Control Of Rvp
RVP900 User Guide M211322EN-J Method Description exitMajorMode_f This routine releases all resources that were allocated during the initialization and execution of the major mode. The EXIT routine is called if the major mode changes, or if we are between modes, for example, after a TTY Chat q command, or a processor reset.
Page 387: Standard Trigger And Antenna Event Example
Appendix C – RVP900 Developer Notes • A specified number of counts of a free running 1 MHz counter (clock time) • A specified number of trigger pulses (trigger relative time) • A specified number of external input line transitions (I/O event time) The callback occurs as soon as the timeout criteria are met for any of the three timers that are activated.
Page 388: Using The Intel Ipp Library
Streaming SIMD Extensions. These technologies can improve the performance of computation intensive signal processing applications. The data types used in the IPP library are mostly compatible with the standard Vaisala typedefs. The IPP routines can almost always be called directly from RVP code. Status codes from the IPP library can be converted to RDA messages with sigIppStatus().
Page 389 Appendix C – RVP900 Developer Notes Vaisala has purchased a single-user developer's license from Intel which allows one engineer to develop code then links to the IPP library, and then to distribute an unlimited number of copies of that code in executable form. The license does not allow any additional programmers to develop their own code as an extension of Vaisala's license.
Page 390 RVP900 User Guide M211322EN-J...
Page 391: Appendix D: Time Series Recording
Tsimport and Tsexport. D.2 TS Record and Playback Software Architecture The TS record and playback features on a local RVP900 and a remote archive host share a common software architecture. The following figure shows the most general case.
Page 392: Figure 59 Iq Data Recording/Playback General Case
This modular design does not make a strong distinction between RVP900 and a separate archive host operating in record or playback mode.
Page 393: Using Rvp Timeseries Api
D.4 Installing and Configuring TS Recording (page 393). RVP900 Processes Collection of processes that are only present on an RVP900 machine. The important functions are: • IQ–Data: writes real time TS to the TS API. These are collected from an IFDR.
Page 394: Attach And Detach Details
RVP900 User Guide M211322EN-J The API is most valuable in providing random access to the recent buffered (I,Q) data and can buffer a couple of seconds of data within the TimeSeries API. This means that programs using the API only need to check the data every 50 to 100 msec without the risk of losing any data.
Page 395: Installing And Configuring Ts Recording
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 systems. Table 117 Required Software for TS Recording...
Page 396: Configuring Automatic Startup Of Tsimport And Tsexport
TSIMPORT: 30780 Each script contain extensive comments and should be edited to suit your configuration. The scripts are shipped configured for the RVP900 end, so you must edit the archive host’s files. You must also edit all tsexport files to explicitly set the target IP address to which it broadcasts the time series.
Page 397: Running Tsimport And Tsexport From The Command Line
Appendix D – Time Series Recording D.4.5 Running tsimport and tsexport from the Command Line You can run tsimport and tsexport from the command line using the following command line options: $ tsimport –help tsimport command line options: – daemon – Run as daemon –...
Page 398: Ts Archive Utility
M211322EN-J Local RVP Real time IQ from the IFDR. This setting is available only on an RVP. Used for normal data processing, to archive local RVP900 real time IQ, or to export real time IQ over the network. Network Used to collect time series from a networked RVP900 or from an archive host using the TS import process.
Page 399: Figure 61 Ts Archive Utility
Appendix D – Time Series Recording Figure 61 TS Archive Utility 1. Log in as operator. 2. Start the TS Archive utility by typing: $tsarchive...
Page 400 • Use the Directory section to select which archive directory to use, or to add another directory. Vaisala recommends you first create the directory from the command prompt. $mkdir /bigdisk/tsarchive • Check Status to see information about the chosen archive directory.
Page 401 Appendix D – Time Series Recording 5. Use Filter area to manage files that are stored on a disk, including displaying data for a certain site, task, and time. Option Description Site Enter a site ID to select data from only one site, or enter the wildcard character to select data from all sites.
Page 402: Software Application Examples
• TS playback on a local RVP900, see D.7.4 TS Playback on a Local RVP900 (page 404). • TS playback from a separate archive host to an RVP900, see D.7.5 TS Playback from a Separate Archive Host to an RVP900 (page 405).
Page 403: Rvp900 In Normal Real-Time Operation
Appendix D – Time Series Recording D.7.1 RVP900 in Normal Real-Time Operation Figure 62 RVP900 in Normal Real-Time Operation In this case, the TS Switch is set to write real-time data from the IQ-Data 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.
Page 404: Ts Recording On A Local Rvp900
Process into the TS API. These are extracted and recorded to local disk by the tsarchive process. While TS data are being recorded, RVP900 may still do its normal data processing tasks, as shown in D.7.1 RVP900 in Normal Real-Time Operation (page 401) Utility Settings •...
Page 405: Figure 64 Ts Record On Separate Archive Host
The advantage of having a separate archive host is that it is easy to install a large disk that is dedicated to time series recording without having record/playback/backup operations interfere with the normal operation of an RVP900. There can be multiple archive hosts on the network.
Page 406: Ts Playback On A Local Rvp900
RVP900 User Guide M211322EN-J D.7.4 TS Playback on a Local RVP900 Figure 65 TS Playback on Local RVP900 In this example, the TS Switch is set to write data from the tsarchive to the TS API. RVP9Proc-n processes then reads the time series data from the API.
Page 407: Ts Playback From A Separate Archive Host To An Rvp900
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, except the TS Switch would be set to write data from the tsimport process.
Page 408: Ts Archive Recording Quick Guide
The Ascope utility is a stand-alone signal processor configuration and plotting utility. When an RVP900 is in playback mode, you can use Ascope to configure the processing of the playback data and display the results. See IRIS and RDA Utilities Guide.
Page 409: Figure 67 Ascope Differences During Rvp900 Ts Playback
When using Ascope during RVP900 playback, the archive can be on the local RVP900 or on a separate archive host. It does not matter where Ascope runs. It can be on the local RVP900 or on a networked host computer through DspExport.
Page 410: Archive On Local Rvp900
RVP900 User Guide M211322EN-J D.8.1 Archive on Local RVP900 Utility Settings The support menus settings for archiving on a local RVP are: • TS Switch: Local Archive • TS Archive: Play Network Note In most cases, you are not sitting up at the radar, so you need to export the displays for these utilities over the network by doing one of the following: •...
Page 411: Ts View Utility
Passive type = TS–Playback When the configuration is complete, you are ready to use IRIS to play back data. 1. Launch tsarchive on your RVP900 machine. 2. Select TS Source to launch the tsswitch. 3. In tsswitch, select Local Playback.
Page 412: Starting Tsview
RVP900 User Guide M211322EN-J This is useful for checking how the data were collected, or to verify that IQ data were recorded. Developers can use tsview software as a model when building their own off-line applications for reading and processing time series data.
Page 413: Tsview Command Line Options
Appendix D – Time Series Recording For the file naming convention, see D.10.3 Tsview Command Line Options (page 411). D.10.3 Tsview Command Line Options -help Gives a list of available options: -count :N (only print N pulses) -data (print data values) -help (print this list and exit) -length :N (max line length to use) -skip :N (skip the first N pulses)
Page 414 The sweeps are indexed 1, 2, 3, ... In 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 sweep rather than azimuth sweep.
Page 415: 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 RVP900 nomenclature, this is called the Acquisition Mode (stored in the rvptsPulseInfo structure). Each time something changes, such as the PRF, the acquisition mode changes, and a new file is created.
Page 416 RVP900 User Guide M211322EN-J File Component Description Each time series sample consists of 2 floating point numbers representing the I and Q voltages. The values are full magnitude with a value of 1. This represents +8 dBm on the IFDR, but may change in future revisions.
Page 417 See dsp.h taskID.iSweep=0 Application sweep number taskID.iAuxNum=0 Application auxiliary number taskID.sTaskName=Ascope_DEFAULT Application task name sSiteName=RVP900 Site name of RVP900 iAqMode=161 Increments each time there is a change iUnfoldMode=0 Dual-PRF flag, see PRF_* in dsp_lib.h iPWidthCode=0 Pulse width index (0–3) fPWidthUSec=1 Pulse width in microseconds fAqClkMHz=35.9751...
Page 418 RVP900 User Guide M211322EN-J rvptsPulseHdr start iVersion=0 iFlags=3 Bit 0: N/A Bit 1: Gap before this pulse Bit 2: First pulse in trigger bank Bit 3: Last pulse in trigger bank Bit 4: Trig bank (possibly unchanged) is just beginning Bit 5:...
Page 419: Appendix E: Serial Status Formats
Appendix E. Serial Status Formats RVP900 can optionally generate an internal BITE packet. Most of these bits are copies of data available from the GPARM command. Those bits are labelled with GP followed by the word number and bit number. See 8.10 Get Processor Parameters (GPARM) (page 271)
Page 420 RVP900 User Guide M211322EN-J Char Function Diagnostic Results 21–27 D6 = GP12, D11 = <spare> D5 = GP12, D10 = <spare> D4 = GP12, D9 = <spare> D3 = GP12, D8 = <spare> D2 = GP12, D7 = <spare> D1 = GP12, D6 = <spare>...
Page 421 Immediate Status 50–56 D6 = GP59, D7 = WSR88D Batch mode is supported D5 = GP59, D6 = Time series data source is external to RVP900 D4 = GP59, D5 = Trigger sequence truncated D3 = GP59, D4 = Using High-SNR packed (I,Q) format...
Page 422 RVP900 User Guide M211322EN-J Char Function Immediate Status 57–63 D6 = GP59, D14 = <spare> D5 = GP59, D13 = <spare> D4 = GP59, D12 = <spare> D3 = GP59, D11 = <spare> D2 = GP59, D10 = Receiver protection fault...
Page 423 Appendix E – Serial Status Formats Char Function SOPRMS Status 0–6 D6 = GP31, D6 = <spare> D5 = GP31, D5 = 3x3 filtering enabled D4 = GP31, D4 = <spare> D3 = GP31, D3 = <spare> D2 = GP31, D2 = Reflectivity speckle remover on D1 = GP31, D1 = Doppler speckle remover on D0 = GP31, D0 = Reflectivity is range normalized, else SNR SOPRMS Status 7–13...
Page 424: Table 123 Internal Qbite Packet (Rvp900 To Host)
RVP900 User Guide M211322EN-J RVP900 can optionally generate this internal QBITE packet. These values are copies of data available from the GPARM command. Regular GPARM values are labelled with GP followed by the word number. Those in the dspExParmIO structure are labelled with EX followed by the word number.
Page 425: Appendix F: Softplane.conf
Appendix F – Softplane.conf Appendix F. Softplane.conf F.1 Configuring the softplane.conf File For manual configuration, configure the softplane.conf file to define pin–by–pin assignment of I/O functions to connectors on the I/O-62 connector panel. The file is a commented plain text ASCII file. Since the RVP and RCP8 have virtually no jumpers, or wirewrap, all I/O configuration on the I/O-62 connector panel is done by software approach according to this file.
Page 426 RVP900 User Guide M211322EN-J • # at the beginning of a line indicates a comment. These are used for internal documentation. If you make changes, comment them, for example: # TTL I/O on J7 # Modification by REP on 2 Apr 03 # Added new interlock input on connector panel J7 pin07 •...
Page 427 Appendix F – Softplane.conf • The first uncommented line of the file indicates the version of the IRIS support software that was last used to machine–generate the file. This is an information-only field for traceability purposes and is not edited. For example: # splConfig.sVersion = "7.32"...
Page 428 RVP900 User Guide M211322EN-J Summary of Description softplane.conf Status and Control Bits sLocal Antenna local mode indicator, usually tied to an external local/remote switch. sStandby Radar ready to radiate indicator sLowerEL Lower limit switch indicator sUpperEL Upper limit switch indicator...
Page 429: Testing, Backup, And Calibration
Appendix F – Softplane.conf • Specify the method of connecting to the I/O-62, for example: splConfig.Io62[0].sExtPanel = "DIRECT" The options are: Connection Type softplane Descriptor DIRECT Direct connect to I/O-62 via 62 pin connector I/O-62 Connector Panel (used for RVP8 and RCP8) IO62CP RVP88D WSR88D connector panel, RVP8 portion WSR88D connector panel, RCP8 portion...
Page 430 RVP900 User Guide M211322EN-J For more information on testing and backing-up the system components, see 1.2 Related Documents (page 13).
Page 431: Appendix G: Rcp903 Asr9-Wsp Panel
G.1 ASR9-WSP with RCP903 ASR9-WSP Panel Overview The ASR9 WSP(weather signal processor) uses RVP900 hardware and software as well as the RVP902-WSP processor, RCP903 ASR9 panel, and RVP901-WSP signal processor. The ASR9 WSP (weather signal processor) is designed to provide a direct replacement to the original RxNet7/RVP7 implementation carrying forward form, fit, and function of the original system wherever physically and logically possible.
Page 432: Power Conditions For Use - Rcp903 Asr9-Wsp
RVP900 User Guide M211322EN-J G.3 Power Conditions for Use - RCP903 ASR9-WSP These operating conditions must be met by the customer installation for the unit to be considered safe in DC power application: RVP900-WSP Subsystem • Components must be installed in a suitable fire enclosure to meet EN60950-1 requirements •...
Page 433: Asr9 Wsp With Rvp900 Panel Architecture
Appendix G – RCP903 ASR9-WSP Panel G.4 ASR9 WSP with RVP900 Panel Architecture The original ASR9 WSP solution was implemented with the Sigmet RxNet7 Model ASR9/ RIM-1 hardware and an RVP7 signal processor. The original design 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.
Page 434: Figure 68 Asr9 Wsp With Rvp7 Architecture
RVP900 User Guide M211322EN-J Figure 68 ASR9 WSP with RVP7 Architecture...
Page 435 WSP Processor are provided. All of the components in Bay 3 are designed to fit in the same area as the original RxNet7 solution. The block diagram for the new RVP900 base ASR9 WSP solution is shown in the following figure and a table with the RVP900-WSP...
Page 436: Rvp901-Wsp Signal Processor Customized For Asr9 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 RVP901-WSP signal processor is Vaisala's standard product offering. When used with ASR9 WSP, it is configured as follows.
Page 437: Rvp902-Wsp Processor Customized For Asr9 Wsp
G.4.2 RVP902-WSP Processor Customized for ASR9 WSP RVP902-WSP Processor is Vaisala's standard product offering with a Xeon X8DTU motherboard running CentOS 6.4, RVP900, and radar utilities. The key features are: • Dual Xeon E5620 Intel 2.4GHz Quad-Core processor with 1333 MHz front side bus •...
Page 438: Rcp903 Asr9-Wsp Panel Physical Interfaces
RVP900 User Guide M211322EN-J • 100/1000 Ethernet running TCP/IP for control and status and UDP packets for I/Q data • WSP #1 and #2 connectors with backward compatible pin out • Serial Port #1 and #2 with backward compatible pass through functionality •...
Page 439: Figure 72 Rcp903 Front Panel Dimensions
Appendix G – RCP903 ASR9-WSP Panel Figure 72 RCP903 Front Panel Dimensions Figure 73 RCP903 Back Panel Dimensions Figure 74 RCP903 Panel Perspective View Mounting Dimensions 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 connector strip with a switch, a power supply for the panel, an Ethernet switch, and the associated cabling.
Page 440: Asr9-Wsp Connector Locations
RVP900 User Guide M211322EN-J Figure 75 RxNet7 Front Panel Figure 76 RCP903 Rack Side Perspective 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 RCP903 Shelf...
Page 441: Rcp903 Asr9-Wsp Electrical Interfaces
Appendix G – RCP903 ASR9-WSP Panel This is intended to mount from the rear of the rack. RCP903 Shelf is mounted directly behind the panel. The rear mounting shelf includes: • Connector strip with a switch (Hammond, 1583H6B1BK POWER STRIP) •...
Page 442: Rvp901-Wsp To Asr9 Radar
TTL signals, and low noise analog signal, are provided by Vaisala. The current cable meets the MIL-DTL-22759/11 specification, which is insulated with PTFE.
Page 443: Rcp903 Asr9-Wsp Panel Interfaces
Direct IF input. Burst sample input VIDEO OUT Video DAC output TRIG-A 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 ASR9-WSP Panel Connectors Defined for Customer's Systems Implementation Connector Size Designator Type...
Page 444: Asr9-Wsp Panel Indicators And Switches
RVP900 User Guide M211322EN-J G.6.4 ASR9-WSP Panel Indicators and Switches The RCP903 Panel has several ASR9-WSP-specific indicators as well as some general status indicator and control switches. Table 130 ASR9-WSP Panel Indicators and Switches Label Location Type Description DATA Between J1 and J2...
Page 445 Appendix G – RCP903 ASR9-WSP Panel Ribbon Signal Name Type Direction Description Number Cable Number NC_WP_SPARE0_P/N 20,4 9,10 Spare No Connect Spare NC_WP_SPARE1_P/N 37,21 11,12 Spare No Connect Spare WP_SX103_P/N 5,38 13,14 RS-422 Input Switch #103 Sense WP_SX104_P/N 22,6 15,16 RS-422 Input Switch #104...
Page 446: J2 Asr9 Interface Wsp #2
RVP900 User Guide M211322EN-J G.6.6 J2 ASR9 Interface WSP #2 Table 132 Pin-out for J2 ASR9 / WSP #2 Ribbon Signal Name Type Direction Description Number Cable Number WP_PRET0_P/N 1,34 RS-422 Input Pretrigger time zero WP_GATE0_P/N 18,2 RS-422 Input Range Gate zero...
Page 447: J3 And J4 Rs-232 Interfaces To Rvp902-Wsp Processor
Appendix G – RCP903 ASR9-WSP Panel G.6.7 J3 and J4 RS-232 Interfaces to RVP902-WSP Processor Table 133 Pin-out for J3 and J4 RS-232 Serial Interface Pin Number Signal Name Type Direction Description No Connect RS-232 RXD (TXD on WSP RS-232 Input Receive Data interface) TXD (RXD on WSP Output...
Page 448: J6 - Rvp901-Wsp Misc Io A To Rcp903 Asr9-Wsp Panel
RVP900 User Guide M211322EN-J G.6.9 J6 - RVP901-WSP Misc IO A to RCP903 ASR9-WSP Panel Table 135 RVP900 Signal Types in CBL210313 Type Destination GPDIFF_PIN_LP/N RS-422 signals TTLIO_PIN/GND TTL signals AMUX_P0/AMUX_N0 Differential analog input A/D signals +5 VDC -5 VDC Ground Table 136 CBL210313 RCP903 Interconnect Cable To RVP901-WSP Misc IO Port A (J3)
Page 449: J7 - Power Interface (Dc)
Appendix G – RCP903 ASR9-WSP Panel RCP903 Signal Name Type Direction RVP901 IFDR Logical Connection Pin Number Number IFDR_HDR_INFO TTL 5V TTL2, GND 13,34 Output 13,31 11_P/N IFDR_HDR_INFO TTL 5V TTL3, GND 14,35 Output 14,32 12_P/N IFDR_HDR_INFO TTL 5V TTL4, GND 15,36 Output 15,33...
Page 450: Asr9 Rim Software Api
RVP900 User Guide M211322EN-J Table 137 Pin-out for J7 Power Input J6 Pin Number Signal Name Description PWR_IN 24 V nominal input power PWR_IN 24 V nominal input power PWR_RETURN Return path (ground) for input power PWR_RETURN Return path (ground) for input...
Page 451: Table 139 Rim Api 6-Level Weather Functions
Appendix G – RCP903 ASR9-WSP Panel Function Name Description rim_pldreset Reboots the board returning it to its original power on state rim_led_clrset Controls the test output LED state rim_board_sw_status_set* Configures the embedded processors performance monitor rim_board_sw_status_get* Returns status of the embedded processors performance rim_board_sw_errlog_set* Configures the boards error message logging functionality rim_board_sw_errlog_get*...
Page 452: Table 141 Rim Api Clock Functions
RVP900 User Guide M211322EN-J Function Name Description rim_get_io_state* Reads the current logic level on all inputs and output pins rim_set_line_state Forces a single output to the user defined level rim_get_line_state Reads the logic level at the pin of the input or output...
Page 453: Table 144 Rim Api Data Processing Controls
Appendix G – RCP903 ASR9-WSP Panel Table 144 RIM API Data Processing Controls Function Name Description rim_asr9_set_run Sets the RCP903 processing state rim_asr9_set_run_cmd Gets the RCP903 processing state that is currently being requested rim_asr9_get_run Gets the RCP903 processing state that is currently running rim_asr9_set_udp_addr* Sets the UDP address and port information for the I/Q...
Page 454: Table 146 Deprecated Functions
RVP900 User Guide M211322EN-J Function Name Description rim_asr9_103104cnt_sim_set Sets the operational mode and simulation override values for the WP_CX103 and WP_CX104 output levels rim_asr9_103104cnt_sim_get Gets the operational mode and simulation override values for the WP_CX103 and WP_CX104 output levels Table 146 Deprecated Functions...
Page 455: Appendix H: Tdwr Customizations
Appendix H – TDWR Customizations Appendix H. TDWR Customizations H.1 TDWR Technical Drawings Figure 81 J1 to J9 Wiring Diagrams...
Page 456: Figure 82 J90 To J111 Wiring Diagrams
RVP900 User Guide M211322EN-J Figure 82 J90 to J111 Wiring Diagrams...
Page 457: Figure 83 J13 Wiring Diagram
Appendix H – TDWR Customizations Figure 83 J13 Wiring Diagram...
Page 458: Tdwr Custom Back Panel
‣ TDWR Custom Back Panel (page 456) H.2 TDWR Custom Back Panel RVP900 can be supplied 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 connectors using a pair of breakout cables. See 4.2.3.1 Generic I/O Interconnect Breakout Cable (page...
Page 459: Table 147 J1 Filter Amp #1
Appendix H – TDWR Customizations The following tables show the signals assigned to the back panel’s 25-pin I/O connectors. Each line in the tables generally describes a pair of signals that should be twisted together for best signal integrity. A common ground is provided on Pin-25 of all 8 connectors. Table 147 J1 Filter Amp #1 Type Direction...
Page 460: Table 150 J4 Transmitter
RVP900 User Guide M211322EN-J Table 150 J4 Transmitter Type Direction Signal Name Comment RFAMPGT/ 4/17 RS-422 Transmitter Trigger RFAMPGTn BPIGT/BPIGTn 5/18 RS-422 Transmitter Trigger PFNGT/PFNGTn 6/19 RS-422 Transmitter Trigger — — Common Ground Table 151 J5 STC #1 Type Direction Signal Name...
Page 461: Softplane.conf File: Rvp900 Tdwr Panel Example
Monitor #1 REX18VB/ 22/24 Analog REX +18V Power REX18VBn Monitor #2 — — Common Ground More Information ‣ TDWR Technical Drawings (page 453) H.3 Softplane.conf File: RVP900 TDWR Panel Example The following example shows RVP900 IFDR-related excerpts from the softplane.conf file.
Page 462 RVP900 User Guide M211322EN-J # Softplane Configuration File # The following general purpose control and status signals: # –––––––––––––––––––– RVP9IFD #0 –––––––––––––––––––– # If you change the in–use flag, run ’softplane –resave’ to rev the choices. splConfig.Rvp9[0].lInUse = 1 # The remote backpanel type must be one of the following: Common : Direct connections using the ’Common I/O’...
Page 463 Appendix H – TDWR Customizations Softplane Configuration File The following general purpose control and status signals can be routed to/from any available hardware pin. The '~' prefix character may be used for signal inversion. Control Outputs Status Inputs cPedAZ[15:0] sPedAZ[15:0] cPedEL[15:0] sPedEL[15:0] cEarthAZ[15:0]...
Page 464 RVP900 User Guide M211322EN-J splConfig.Io62[0].Opt.Cp.J1.pin16 = "sPedAZ[15]" splConfig.Io62[0].Opt.Cp.J1.pin17 = "" splConfig.Io62[0].Opt.Cp.J1.pin18 = "" splConfig.Io62[0].Opt.Cp.J1.pin19 = "" splConfig.Io62[0].Opt.Cp.J1.pin20 = ""# TTL/CMOS on J2 splConfig.Io62[0].Opt.Cp.J2.pin01 = "cEarthAZ[0]" splConfig.Io62[0].Opt.Cp.J2.pin02 = "cEarthAZ[1]" splConfig.Io62[0].Opt.Cp.J2.pin03 = "cEarthAZ[2]" . . . splConfig.Io62[0].Opt.Cp.J2.pin15 = "cEarthAZ[14]" splConfig.Io62[0].Opt.Cp.J2.pin16 = "cEarthAZ[15]"...
Page 465 Appendix H – TDWR Customizations splConfig.Io62[0].Opt.Cp.J7.pin17 = "sAux[16]" splConfig.Io62[0].Opt.Cp.J7.pin18 = "sAux[17]" splConfig.Io62[0].Opt.Cp.J7.pin19 = "sAux[18]" splConfig.Io62[0].Opt.Cp.J7.pin20 = "sAux[19]" # Eight IO62 line pairs on J3 splConfig.Io62[0].Opt.Cp.J3_01_14.lRS422 = 0 splConfig.Io62[0].Opt.Cp.J3_01_14.iTerm = 0 splConfig.Io62[0].Opt.Cp.J3_01_14.pinPos = "cPWidth[0]" splConfig.Io62[0].Opt.Cp.J3_01_14.pinNeg = "cPWidth[1]" splConfig.Io62[0].Opt.Cp.J3_02_15.lRS422 = 0 splConfig.Io62[0].Opt.Cp.J3_02_15.iTerm = 0 splConfig.Io62[0].Opt.Cp.J3_02_15.pinPos = "cRadiateOn"...
Page 466 RVP900 User Guide M211322EN-J splConfig.Io62[0].Opt.Cp.J9_03_16.pinPos = "sLocal" splConfig.Io62[0].Opt.Cp.J9_03_16.pinNeg = "sStandby" splConfig.Io62[0].Opt.Cp.J9_04_17.lRS422 = 0 splConfig.Io62[0].Opt.Cp.J9_04_17.iTerm = 1 splConfig.Io62[0].Opt.Cp.J9_04_17.pinPos = "sLowerEL" splConfig.Io62[0].Opt.Cp.J9_04_17.pinNeg = "sUpperEL" splConfig.Io62[0].Opt.Cp.J9_05_18.lRS422 = 0 splConfig.Io62[0].Opt.Cp.J9_05_18.iTerm = 0 splConfig.Io62[0].Opt.Cp.J9_05_18.pinPos = "" splConfig.Io62[0].Opt.Cp.J9_05_18.pinNeg = "" splConfig.Io62[0].Opt.Cp.J9_06_19.lRS422 = 0 splConfig.Io62[0].Opt.Cp.J9_06_19.iTerm = 0 splConfig.Io62[0].Opt.Cp.J9_06_19.pinPos = ""...
Page 467: Appendix I: References And Credits
Appendix I – References and Credits Appendix I. References and Credits • Dazhang, T., S.G. Geotis, R E. Passarelli Jr., A.L. Hansen, and C.L. Frush, 1984: Evaluation of an Alternating–PRF Method for Extending the Range of Unambiguous Doppler Velocity. Preprints of the 22nd Conference on Radar Meteorology, American Meteorological Society, 523-527.
Page 468 RVP900 User Guide M211322EN-J...
Page 469: Glossary
Glossary Glossary automatic frequency control. See also, DAFC (page 468). Automatic Gain Control. The gain of the linear channel video signals is adjusted based on an estimate of the next signal level. For example using the average power of the last few pulses at that range.
Page 470 RVP900 User Guide M211322EN-J DAFC Digital Automatic Frequency Control. Discrete Fourier Transforms Doppler spectrum width The standard deviation of the Doppler spectrum in m/s. The spectrum width is a measure of the shear and turbulence in the radar pulse volume at a given range. See...
Page 471 Glossary GC/AP Ground clutter and anomalous propagation GMAP Gaussian model adaptive processing Intermediate Frequency. IFDR Intermediate Frequency Digital Receiver. ingest file A disk file of raw polar coordinate data that is collected during the execution of a task. Ingest files are used for subsequent product generation. See also RAW product (page 470).
Page 472 Radar Control Processor. Takes care of, for example, antenna movements. Radar Data Acquisition software used in RVP900 Radio frequency radar product generator...
Page 473 Glossary Signal Quality Index (SQI) The autocorrelation of the received signal at lag 1 divided by lag zero. This is a number in the range [0,1] where 1 is the perfect Doppler point target and 0 is white noise. Typically used for thresholding velocity and width at a level of ~0.3...0.4. signal-to-noise ratio STALO Stable Local Oscillator.
Page 474: Index
RVP900 User Guide M211322EN-J Index setup..............350 timing, adjust............136 AFC...............50, 93, 137 tracking..............177 adjusting..............147 burst pulse analysis functional test............ 359 amplitude............... 42 set................311 frequency............... 42 SETAFC..............311 phase............... 42 setup..............350 burst spectra............137 test mode...............151 algorithms..............169 customize..............371 calibration..............362 develop..............371 clutter correction..........206...
Page 475 Index debug options............351 analog..............60 DFT processing............46 discrete..............60 diagnostics interconnect breakout cable......58 SLED...............300 I and Q processing..........23 IFDR............21, 23, 107, 116 digital front end AFC..............137, 147 configure.............. 130 AFC motor............101 plot commands..........130 AFC test mode.............151 digital transmitter............29 digital waveform............333 ambiguity spectra plot........160...
Page 476 RVP900 User Guide M211322EN-J IF processing............174 NOP................237 IF receiver specifications............331 IF receiver, upgrade opcode IFDR................55 custom opcodes..........323 IF signal conversion..........171 USRCONT..............323 IF signal processing........23, 172 USRINTR..............323 input IF signal............360 XARGS..............306 install................339 opcodes checklist..............
Page 477 Io calibration......217 range mask............303 regulatory compliances range averaging............44 China RoHS.............16 processing............200 RCP903 ASR9-WSP panel..... 16, 429 range resolution............. 154 RVP900..............16 WEEE................16 CFGHDR..............308 RHOH header..............308 verify..............232 ray synchronization RHOHV angle boundaries..........189 verify..............
Page 478 RVP900 User Guide M211322EN-J RCP903 ASR9-WSP panel........16 modify..............92 RVP900..............16 modulations............126 phase control..........102, 126 signal processing..........329 saved................88 RVP900 transmissions............126 China RoHS.............16 triggers..............113 expansion panels..........50 Tx Synthesis............122 regulatory compliances........16 SIG................206 RVP901 signal generator TxDAC stand-alone bench test....367...
Page 479 Index TASKID................ 317 tsexport............394, 395 tsimport............394, 395 TDWR................ 456 tsswitch..............395 technical drawings........... 453 tsview............409–411 terminal UDP ports............393 setup..............343 UIQBITS..............314 setup check procedure........344 test................339 timing................22 checklist...............340 trademarks..............14 I/O................250 transmitter phase control IOTEST..............250 setup..............352 OTEST..............
Page 480 RVP900 User Guide M211322EN-J unfolding..............45 velocity unfolding dual PRF............... 222 view card................89 system status............89 Vp..................91 warranty hardware..............waveform..............152 waveforms trigger generator..........293 weather Signal Power autocorrelation..........206 threshold..............206 weather signal processing........40 wide dynamic range..........62...
Page 481: Hardware Limited Warranty
User Guide documentation for a period of one year following delivery. In the event of a failure during the warranty period, the customer should notify Vaisala to obtain a Return Authorization. Upon receiving the Return Authorization from Vaisala, the customer ships the failed unit by pre-paid freight.
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