双向加窗技术下多普勒天气雷达回波信号识别系统设计

Design of Doppler Weather Radar Echo Signal Recognition System using Bidirectional Windowing Technology

摘要:

多普勒天气雷达是一种利用多普勒效应探测大气中粒子运动状态和速度的雷达系统。由于距离分辨率限制和目标反射的复杂性，多普勒雷达在接收信号时会出现不同距离上回波信号的混叠问题，难以捕捉到全面的频谱信息，影响了对天气现象的监测效果。为此，设计双向加窗技术下多普勒天气雷达回波信号识别系统。通过改装设计天线/馈线、雷达发射机、雷达接收机等元件，优化多普勒天气雷达回波信号生成器；加设信号滤波器，优化信号处理器的工作方式，完成系统硬件部分的优化设计。系统软件设计上，通过同步采样技术和编码技术，构建系统数据库表和逻辑连接，完成识别系统回波信号低延时采集和高效存储；采用矩形窗和汉宁窗双向加窗技术抑制背景噪声和杂音，提高信号的清晰度，完成对初始回波信号的处理，基于蝶形运算从时域和频域两个方面综合提取信号特征；根据不同气象条件下回波信号特征，设置多普勒天气雷达回波信号识别标准；根据标准特征匹配结果得出识别结果，完成多普勒天气雷达回波信号双向加窗识别系统设计。通过系统测试得出结论:优化设计系统的误识率降低了2.55%，系统误识率波动幅值能够控制在0.5%以下，即优化设计系统在识别功能和运行性能两个方面具有明显优势。

Abstract:

Doppler weather radar is a radar system that uses the Doppler effect to detect the motion state and velocity of particles in the atmosphere. Due to the limitation of distance resolution and the complexity of target reflection, Doppler radar may encounter the problem of aliasing of echo signals at different distances when receiving signals, making it difficult to capture comprehensive spectral information, which affects the monitoring effect of weather phenomena. To this end, design a Doppler weather radar echo signal recognition system using bidirectional windowing technology. Optimize the Doppler weather radar echo signal generator by modifying and designing components such as antennas/feeders, radar transmitters, and radar receivers; Add signal filters, optimize the working mode of the signal processor, and complete the optimization design of the system hardware. In terms of system software design, synchronous sampling technology and coding technology are used to construct system database tables and logical connections, completing low latency acquisition and efficient storage of echo signals in the recognition system; Using rectangular and Hanning window bidirectional windowing techniques to suppress background noise and noise, improve signal clarity, and complete the processing of initial echo signals. Based on butterfly operation, signal features are comprehensively extracted from both time and frequency domains; Set Doppler weather radar echo signal recognition standards based on the characteristics of echo signals under different meteorological conditions; Based on the standard feature matching results, the recognition results are obtained, and the design of a bidirectional windowed recognition system for Doppler weather radar echo signals is completed. The conclusion drawn from system testing is that the error recognition rate of the optimized design system has been reduced by 2.55%, and the fluctuation amplitude of the system error recognition rate can be controlled below 0.5%, indicating that the optimized design system has obvious advantages in recognition function and operational performance.