微波信号海面超视距传播的建模和实验分析

摘要

介绍了雷达信号的海面传播特性,给出了抛物方程和射线追踪方法,讨论了出现概率较高的海洋环境:蒸发波导、表面波导和悬空波导,及相应的折射率剖面.研究了和距离有关的电波环境,比较两种模型算法在不同大气条件下、不同频段的电波传播特性结果,同时给出了实验分析结果.结果表明:射线追踪法能给出场模式的合理定性图,较抛物方程法,具有直观和计算速度快的优点,尤其在视距范围内更适用.%The characteristics of microwave oversea propagation are discussed briefly. The split— step FFT parabolic equation and ray tracing model are described firstly. The commonly encountered ocean environments are considered indrding evaporation ducts, surface and elevated ducts, given by bilinear and trilinear refractivity profiles. PE results are compared with the ray tracing. Examples involving measurements in China East Sea are given. Results show that ray tracing method can give the proper qualitative analysis to the PE.