机载前视风切变雷达信号处理方法分析

Analysis of Signal Processing Technology of Airborne Forward-looking Windshear Weather Radar System

遭遇低空风切变是飞机失事的主要原因之一,利用机载气象雷达探测危险低空风切变的最大难题在于寻求一种好的信号处理算法,在气象信号回波功率远低于地杂波回波功率时仍有好的性能表现。介绍了机载前视风切变雷达的几种数字信号处理算法,重点讨论了脉冲对处理(PPP)法和傅立叶变换(FFT)法,分析了两种算法的原理特点,采用风切变回波模拟数据对两种算法进行了计算机仿真和性能对比分析,仿真结果表明,在一般情况下采用FFT和PPP方法估计风速的性能差异不大,在微下击暴流核心区域,都能获得对风速的良好估计。

Airborne weather radar is developed to detect hazardous low altitude windhear which is a major contributing factor in many airline crashes. One of the major challenges is to develop an excellent signal processing algorithm which will perform satisfactorily when the weather return signal power is far lower than ground clutter return power. This thesis discussed the signal processing technology of airborne forward - looking windshear weather radar system. Pulse Pair Processing（PPP） and Fast Fourier Transform （FFT） processing methods are introduced in detail. The principles of the two methods are analyzed and simulated using microburst echo signal data. The simulation results show that the performance of the two methods was not much different. In the core area of windshear, they both have good wind speed estimation.