基于物理模型的双极化多普勒天气雷达回波模拟

Dual Polarization Dopplerweather Radar Echo Simulation based on a Physical Model

利用降水回波的物理特性模拟回波,可以为天气雷达提供接近真实的测试信号,节省了天气雷达研发、维护的时间和成本。双极化天气雷达测量降雨的理论依据于水滴是扁椭球形。雨滴大小采用指定的Marshal-Palmer分布描述,并且其均匀分布于由雷达参数所决定的雷达分辨率体积内,回波信号就是所有雷达分辨率体积内散射电场的叠加。通过分析双极化天气雷达回波特性,建立回波的数学模型。该模拟方法的输入是雨滴参数、标准天气雷达参数、风速和角度值。输出参数是I、Q回波的电压形式,该模型有效地模拟了降水散射体的回波,也表明基于空间物理特性的双极化天气雷达模拟是能够实现的。

Weather radar echo signal can be simulated by using the physical characteristics of rainfall.The simulation signalused as test signal in radar research and developmentcan save time and money.The theoretical basis of dual polarizationDoppler weather radar is that the raindrops areoblate spheroid.Theraindrops size distributionfitsthe Marshall-Palmerraindrop spectra.The raindropsare uniformly distributed throughout the radar resolution volume determined by radar parameters.Theecho signal can be explained as a superposition of the scattered electric fields in the volume.A mathematical model of echo signal is establishedby analyzing the echo characteristics of dual polarization Dopplerweather radar.The inputs of this model are raindrop parameters,radar parameters,wind speed and azimuth of the volume.The output is I,Q electric voltage sequences.This model simulates the rainfall radar echo signal efficiently,meanwhile,it shows that the simulation of dual polarization Dopplerweather radar echo signal based on physical characteristics can be realized.