基于压缩感知的无源雷达超分辨DOA估计

摘要

波达方向(DOA)信息是目标定位过程中一个非常重要的量。但是在无源雷达中，目标回波通常掩盖在强直达波、多径干扰以及噪声的背景之下，因此很难对其进行DOA估计，特别是在多目标的情况下。该文提出一种基于压缩感知的无源雷达超分辨DOA估计方法，为了消除直达波和多径干扰以及提高目标回波的信噪比，首先进行时域干扰相消和距离-多普勒2维相关处理，最后在目标对应的距离-多普勒单元处进行方位向压缩感知稀疏重构，以获得目标的DOA信息。仿真分析表明，该文方法能够在无源雷达中进行有效的超分辨DOA估计。%The information of target’s Direction Of Arriving (DOA) is very important for target location. But in passive radar, the weak target echoes are usually embedded in the background of strong direct signal, multipath and noise. So it is very difficult to estimate the DOA of target in passive radar, especially when there are multiple targets. In this paper, a method based on compressed sensing is proposed to perform high resolution DOA estimation in passive radar. In order to remove the strong direct signal and multipath and improve the SNR of targets, first the temporal interference cancellation and range-Doppler 2D correlation are utilized. Finally, the signal of targets’ delay-Doppler bin is reconstructed according to DOA using reconstruction algorithm of compressed sensing. Simulation results show that the proposed method can perform the super-resolution DOA estimation in passive radar.