Shen Xi, Huang Defeng David
Department of Electrical, Electronic and Computer Engineering, The University of Western Australia, Perth 6009, Australia.
Sensors (Basel). 2021 Sep 24;21(19):6389. doi: 10.3390/s21196389.
In this paper, a novel approach for raindrop size distribution retrieval using dual-polarized microwave signals from low Earth orbit satellites is proposed. The feasibility of this approach is studied through modelling and simulating the retrieval system which includes multiple ground receivers equipped with signal-to-noise ratio estimators and a low Earth orbit satellite communicating with the receivers using both vertically and horizontally polarized signals. Our analysis suggests that the dual-polarized links offer the opportunity to estimate two independent raindrop size distribution parameters. To achieve that, the vertical and horizontal polarization attenuations need to be measured at low elevation angles where the difference between them is more distinct. Two synthetic rain fields are generated to test the performance of the retrieval. Simulation results suggest that the specific attenuations for both link types can be retrieved through a least-squares algorithm. They also confirm that the specific attenuation ratio of vertically to horizontally polarized signals can be used to retrieve the slope and intercept parameters of raindrop size distribution.
本文提出了一种利用低地球轨道卫星的双极化微波信号反演雨滴大小分布的新方法。通过对反演系统进行建模和仿真来研究该方法的可行性，该反演系统包括多个配备信噪比估计器的地面接收器以及一颗与接收器使用垂直极化和水平极化信号进行通信的低地球轨道卫星。我们的分析表明，双极化链路提供了估计两个独立雨滴大小分布参数的机会。为实现这一点，需要在低仰角处测量垂直极化和水平极化衰减，此时它们之间的差异更为明显。生成了两个合成雨场来测试反演性能。仿真结果表明，两种链路类型的比衰减都可以通过最小二乘法算法反演得到。结果还证实，垂直极化与水平极化信号的比衰减可用于反演雨滴大小分布的斜率和截距参数。
