强杂波背景下穿墙成像雷达多径虚像抑制

Multipath Virtual Image Suppression of Through-the-Wall Imaging Radar Under Strong Clutter Background

在穿墙雷达成像中,侧墙与目标、后墙之间反射产生的多径虚像与杂波严重干扰了目标检测成像。本文首先建立了此类虚像和杂波形成的场景模型,并构建目标和墙体之间的多径传播模型,以此为基础给出选取子孔径的基本准则。然后基于子孔径图像相乘的原理,提出伽马校正的方法,即根据图像对比度的比例关系获得每个子图像指数权值并将加权的子图像进行连乘,从而达到抑制多径虚像与强杂波的效果。最后给出实验仿真和相应的分析,目标信杂比有了明显提高。

In through-the-wall radar imaging,the multipath virtual image and clutter can be generated due to the reflection between the side wall,the target and the back wall,which seriously interferes with the target detection and imaging.In this paper,we firstly establish the scene model of such virtual image and clutter and construct the multipath propagation model between the target and the wall.On the basis,we give the basic criteria of selecting sub-apertures.Then,a gamma correction method is proposed based on the principle of sub-apertures image multiplication.That is,each sub-image index weight is obtained according to the proportional relationship of image contrast and the weighted sub-images are multiplied,which achieves the effect of suppressing multipath virtual images and strong clutter.Finally,experimental simulation and corresponding analysis are given,and the target-to-clutter ratio is significantly improved.