摘要
针对雨云等分布式目标特点,分析得出SAR测量降水的方位向分辨率与降水粒子多普勒速度标准差之间正线性相关。然后以理想雨云单元(即充塞系数为1)为例,提出一种考虑电磁波对散射回波衰减作用下有效地表及降水体散射回波计算方法,并比较了考虑衰减与不考虑衰减两种情况下降水回波信杂比(Signal to Clutter Ratio,SCR)的差异。仿真结果表明地表面散射回波对多普勒速度标准差的变化更敏感,强降水天气下,雨云对降水回波的衰减作用不可忽略,这一特性适用于从雷达接收到的后向散射回波中分离地表杂波的影响。
According to the characteristics of distributed targets such as rain clouds,it is concluded that there is a positive linear correlation between the azimuth resolution of precipitation SAR and the standard deviation of the precipitation velocities.Then,signals consisted by the echo from surface and precipitation cell is shown with the ideal precipitation cloud cell(ie,the congestion coefficient of 1),and a simulation method is proposed to calculate the effective scattering signals under the attenuation effect of the electromagnetic wave.At the same time,the difference of signal to clutter ratio(SCR)while considering the attenuation and not considering the attenuation in both cases is analyzed in this paper.Simulation results show that the surface scattering echo is more sensitive to the change of the standard deviation of the precipitation velocities and the attenuation effect of precipitation cloud cannot be neglected under heavy rainfall.
出处
《工业控制计算机》
2018年第12期82-84,共3页
Industrial Control Computer
基金
国家卫星气象中心创新基金项目(400120109031047)
关键词
分布式目标
多普勒速度标准差
方位向分辨率
散射回波
衰减
distributed target
standard deviation of the precipitation velocities
azimuth resolution
scattering signals
attenuation
