CN-122017848-A - Dual-polarization rainfall radar signal processing method and system

CN122017848ACN 122017848 ACN122017848 ACN 122017848ACN-122017848-A

Abstract

The application provides a method and a system for processing a dual-polarization rainfall radar signal, relates to the field of weather radars, and solves the problems of poor expansibility, insufficient flexibility and poor self-adaptability in the prior art that a FPGA and a DSP hardware processing board are adopted to process a rainfall signal in a Doppler mode. The method specifically comprises the steps of obtaining dual-polarization echo signals, preprocessing the dual-polarization echo signals, carrying out orthogonal demodulation and digital processing on the dual-polarization echo signals to obtain dual-polarization channel IQ data, carrying out multi-thread parallel processing on the dual-polarization channel IQ data to generate weather product data and processing state data packets, carrying out hierarchical processing on the state data packets to generate control instructions, and dynamically adjusting the multi-thread parallel processing process according to the control instructions. The application can reduce the limitation of hardware equipment to the signal processing process by generating the dual-polarized channel IQ data, and can dynamically adjust the multithread parallel processing process by the control instruction, thereby improving the flexibility and the adaptability of the signal processing.

Inventors

LI YATING
Jia Jiaming
WU XIAOYAN
LI JUAN
WU YANAN
FANG JIEKE

Assignees

四创电子股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260128

Claims (10)

1. The method for processing the double-polarization rainfall radar signal is characterized by comprising the following steps of: acquiring a double-polarization echo signal received by a radar antenna, and preprocessing the double-polarization echo signal; orthogonal demodulation and analog-to-digital conversion processing are carried out on the preprocessed dual-polarization echo signals, so that dual-polarization channel IQ data of a horizontal polarization H channel and a vertical polarization V channel are obtained; Carrying out multi-thread parallel processing on the dual-polarized channel IQ data to generate a processing state data packet and a final meteorological product, wherein the processing state data packet comprises processing results of all steps in the multi-thread parallel processing; generating a control instruction after grading the processing state data packet; And dynamically adjusting the multithreading parallel processing process according to the control instruction.
2. The method for processing dual-polarized rainfall radar signal according to claim 1, wherein the acquiring manner of the IQ data of the dual-polarized channel comprises: demodulating the double-polarization echo signals preprocessed by the same clock source and the local oscillation signals to obtain synchronous intermediate frequency signals; Mixing the synchronous intermediate frequency signal with two paths of homologous local oscillation signals with orthogonal phases respectively to obtain I/Q analog signals of an H channel and a V channel, wherein I is an in-phase component, Q is a quadrature component, and the homologous local oscillation signals comprise a local oscillation signal in-phase with a main local oscillation and a local oscillation signal orthogonal with the main local oscillation phase; And carrying out analog-to-digital conversion on the I/Q analog signals of the H channel and the I/Q analog signals of the V channel under the same clock edge to obtain dual-polarized channel IQ data of the horizontal polarization H channel and the vertical polarization V channel.
3. The method for processing the dual-polarization rainfall radar signal according to claim 1, wherein the multi-thread parallel processing comprises pulse compression processing, coherent accumulation processing, filtering processing, parameter calculation processing, quality control processing and parameter configuration processing; The pulse compression processing is used for obtaining a one-dimensional range profile sequence from the dual-polarized channel IQ data through matched filtering processing; The coherent accumulation processing is used for performing coherent superposition on the one-dimensional range-profile sequence to obtain a range-Doppler data matrix; The filtering process is used for filtering the distance Doppler data matrix to obtain a meteorological signal spectrum with clutter components filtered; The parameter calculation process is used for carrying out spectrum distance calculation, autocorrelation estimation and double-polarization parameter calculation on the meteorological signal spectrum with clutter components filtered to obtain meteorological base data, wherein the meteorological base data comprises reflectivity factors, radial speed, spectrum width, differential reflectivity, differential phase constants, correlation coefficients, signal-to-noise ratio, quality factors SQI and quality factors CCOR; the quality control process is used for deleting meteorological base data by adopting distance average and extracting quality factors SQI and quality factors CCOR to control output parameters so as to obtain quality-controlled meteorological product data; the control output parameters comprise that invalid values lower than a threshold value in the meteorological base data are removed according to the quality factor SQI and the quality factor CCOR value setting judgment threshold value, the quality factor SQI and the quality factor CCOR are used as weight factors, and the meteorological base data with the invalid values removed are subjected to weighted average calculation to obtain quality-controlled meteorological product data; The parameter configuration process is used for correcting noise of the weather product data after quality control by adopting actual radar measurement parameters and correcting the weather product data after quality control to obtain a final weather product; And integrating the pulse compression processing, the coherent accumulation processing, the filtering processing, the parameter calculation processing and the quality control processing results into a processing state data packet.
4. The method for processing the dual-polarization rainfall radar signal according to claim 1, wherein the processing state data packet is classified to generate a control command, and the classifying processing includes: Extracting and calculating characteristic parameters from the processing state data packet, wherein the characteristic parameters comprise signal-to-noise ratio SNR, average correlation coefficient rhohv, reflectivity gradient, data intensity, power spectrum and quality factor; Comparing and matching the characteristic parameters with scene rules and quality thresholds in a preset knowledge base; And generating a control instruction containing a specific adjustment action according to the matching result, wherein the control instruction comprises an instruction type, a parameter set and a condition or range for the instruction to take effect.
5. The method of claim 3, wherein the control instructions dynamically adjust the multi-threaded parallel processing process, comprising selecting a filtering algorithm, setting a quality factor, switching to a corresponding rainfall detection mode, and adjusting parameter configuration according to the corresponding rainfall detection mode, wherein the filtering algorithm comprises clutter map construction, an adaptive spectrum filtering algorithm and an IIR filtering algorithm.
6. The method of claim 5, wherein the quality factors include SQI quality factors and CCOR quality factors; The SQI quality factor is calculated by the following formula: Calculating; Is the signal-to-noise ratio, W is the spectral width, Is a function of the spectral width, for a pure sinusoidal signal with a spectral width of zero, Is that Is a function of (2).
7. The method of claim 6, wherein the CCOR quality factor is calculated by: According to calculations Value and preset Comparing the threshold values; When calculated Greater than or equal to a preset value Threshold time by calculation Calculation of The quality factor, wherein, Is the intensity of the data that is to be transmitted, Is a power spectrum; When calculated Less than a preset value Threshold time by calculation Calculation of The quality factor, wherein, C is clutter power, S is signal power, , N is the power of the noise and the power of the noise, Is the statistic obtained by performing first-order autocorrelation operation on the dual-polarization echo signals.
8. The method of claim 5, wherein the switching to the corresponding rainfall detection mode includes selecting one of predefined rainfall detection modes and generating a corresponding control command according to a result of comparison matching of the characteristic parameters with scene rules in a preset knowledge base and quality thresholds; the predefined rainfall detection pattern comprises: A conventional precipitation monitoring mode, a strong convection monitoring mode, a heavy rain quantitative estimation mode and a weak precipitation observation mode; the rainfall detection mode is used for associating different parameter sets, wherein the parameter sets comprise pulse repetition frequency, beam scanning strategy, coherent accumulation pulse number, a filtering algorithm preset for the selected rainfall detection mode and a quality factor threshold.
9. The method of claim 7, wherein the adjusting the parameter configuration comprises: When calculated Less than a preset value When the threshold value is reached, performing deviation correction on the weather product data after quality control based on the noise power N measured by the actual radar; Performing gain and phase compensation correction on the relative intensity deviation and the phase deviation between the horizontal polarization H channel and the vertical polarization V channel; the noise power based bias correction includes: subtracting the noise power from the autocorrelation estimate by the signal power to obtain a corrected signal power estimate By calculation Respectively calculating and obtaining deviation signal-to-noise ratio values of a horizontal polarization H channel and a vertical polarization V channel And ; The differential reflectance ZDR is calculated from The calculation and correction are carried out to obtain, The correlation coefficient According to calculation type And (5) calculating and correcting.
10. The double-polarization rainfall radar signal processing system is characterized by comprising a digital receiving and transmitting system, a software signal processing system and a monitoring terminal system; The digital transceiver system is used for acquiring dual-polarization echo signals received by the radar antenna, and performing preprocessing, orthogonal demodulation and digital processing to obtain synchronous IQ data of the horizontal and vertical dual-polarization channels; The signal processing system is used for carrying out software parallel processing on the synchronous IQ data so as to generate a processing state data packet and a final meteorological product; The monitoring terminal system is used for generating a control instruction after carrying out hierarchical processing on the processing state data packet, and dynamically adjusting the multithreading parallel processing process according to the control instruction.

Description

Dual-polarization rainfall radar signal processing method and system Technical Field The invention belongs to the field of weather radar, relates to radar signal processing technology, and particularly relates to a double-polarization rainfall radar signal processing method and system. Background The rainfall radar is core equipment for monitoring regional precipitation and early warning flood disasters. The performance of the signal processing system directly determines the accuracy and reliability of the final weather product (e.g., intensity, speed, precipitation rate). The traditional rain radar signal processing system is mostly based on Doppler rain radar realized by a FPGA (field programmable gate array) and a DSP (digital signal processor) hardware processing board card. The architecture has higher efficiency in processing deterministic tasks, but has obvious limitations of firstly, fixed and limited hardware resources (such as logic units and memories), which lead to difficult algorithm function expansion and difficult integration of more complex processing flows such as double polarization parameter calculation, and secondly, the algorithm and hardware are deeply coupled, which lead to long period, high cost and insufficient flexibility of post-update, optimization or reconstruction of the processing flows for different scenes. The application provides a method and a system for processing a dual-polarization rainfall radar signal, which solve the technical problems of poor expansibility, insufficient flexibility and incapability of self-adaptive adjustment according to scenes in a curing processing architecture in the prior art. In order to solve the technical problems, the application adopts the following technical scheme: In a first aspect, a method for processing a dual-polarization rainfall radar signal is provided, including: The method comprises the steps of obtaining dual-polarization echo signals received by a radar antenna, preprocessing the dual-polarization echo signals, carrying out orthogonal demodulation and analog-to-digital conversion on the preprocessed dual-polarization echo signals to obtain dual-polarization channel IQ data of a horizontal polarization H channel and a vertical polarization V channel, carrying out multi-thread parallel processing on the dual-polarization channel IQ data to generate a processing state data packet and a final weather product, wherein the processing state data packet comprises processing results of all steps in the multi-thread parallel processing. And dynamically adjusting the multithreading parallel processing process according to the control instruction. Based on the technical scheme, in the dual-polarization rainfall radar signal processing method provided by the application, the full-software parallel processing architecture is adopted to replace the traditional FPGA/DSP hardware curing process, so that the optimization of general-purpose logic driving is realized from the system level, and the core problems of poor expansibility and difficult algorithm updating of the traditional architecture are solved. The method not only allows a flexible set of complex algorithm modules, but also can be used for comparing and matching based on the real-time output processing state data packet and the scene rule and the quality threshold in the preset knowledge base, thereby realizing the dynamic adjustment of the processing flow and the resource scheduling at the logic level and laying the foundation of high real-time performance and strong self-adaptability of the method. With reference to the first aspect, in one possible implementation manner, the acquiring manner of the IQ data of the dual-polarized channel includes: demodulating the double-polarization echo signals preprocessed by the same clock source and the local oscillation signals to obtain synchronous intermediate frequency signals; Mixing the synchronous intermediate frequency signal with two paths of homologous local oscillation signals with orthogonal phases respectively to obtain I/Q analog signals of an H channel and a V channel, wherein I is an in-phase component, Q is a quadrature component, and the homologous local oscillation signals comprise a local oscillation signal in-phase with a main local oscillation and a local oscillation signal orthogonal with the main local oscillation phase; And carrying out analog-to-digital conversion on the I/Q analog signals of the H channel and the I/Q analog signals of the V channel under the same clock edge to obtain dual-polarized channel IQ data of the horizontal polarization H channel and the vertical polarization V channel. With reference to the first aspect, in a possible implementation manner, the multithreading parallel processing includes a pulse compression processing, a coherent accumulation processing, a filtering processing, a parameter calculation processing, a quality control processing and a parameter configuration processing; The puls