多径效应对信号接收及方向测量的影响

在论述L阵干涉仪和圆阵相关法测向体制误差形成的基础上，基于电磁波传播的多径效应，建立了地空无线链路四径传输模型，并将单个多径分量用时延相同的多径簇来描述，分析了多径分量和多径簇对单个天线接收信号相位和不同天线接收信号互相关系数造成的影响。仿真结果表明，多径条件下接收信号的波形、频谱和相位谱较直射信号都将发生显著的变化，多径效应对俯仰角造成的测量误差要大于对方位角造成的测量误差。

Influence of Multipath Effect on Signal Receiving and Direction Finding

Through analysing the direction finding(DF) error of phase interferometer by L array and correlation method by circular array, the air ground channel multipath transmission four ray model is established, and single multipath ray is described by the same time delay multipath clusters.The influence of multipath ray and multipath clusters on the phase of single antenna receiving signal and cross correlation coefficient of multi antennas receiving signal is analysed. The simulation results show that waveform, frequency spectrum and phase of receiving signal change remarkably compared with direct transmission signal in the multipath condition, and the measurement error of pitch angle caused by multipath effect is larger than that of azimuth.