基于墙体参数估计的穿墙成像与校正算法

An Algorithm of Through-Wall Imaging and Correction Based on the Estimation of Wall Parameters

墙体对电磁波的传播具有折射与多次反射作用,若采用传统的雷达成像方法,则会造成墙后目标的偏移与散焦。通过分析墙体与墙后目标对步进频连续波信号的回波特性,提出了一种基于墙体参数估计的穿墙雷达成像与校正算法。该方法首先根据墙体回波的距离向压缩结果划定墙体相对介电常数与厚度的估计范围,并利用估计范围内的参数取值构造补偿因子,然后通过比较补偿后墙后目标的聚焦效果来确定墙体参数的具体值。仿真结果与实验结果表明,该方法能够在系统离墙较远的条件下实现墙体参数的估计,同时完成墙后目标的准确成像。

Due to the refraction and multi-reflection of electromagnetic wave spread caused by the wail, the target behind the wall will become shifted and unfocused by using traditional imaging methods. In this paper, a stepped-frequency-continuous-wave（SFCW） signal is applied to through-wall detection, and the corre- sponding algorithm for imaging and correction is proposed. To begin with, wall reflection is modeled and the estimation range of wall parameters is acquired. According to wall transmission model, compensation coefficients are constructed with numerical values within the estimation range. Finally, real values of wall parameters are selected through the refocusing degree of compensated images. Simulation and experiment results show that the proposed algorithm is able to realize precise target imaging and wall parameters estimation simultaneously when antenna array is 12.6 m away from the wall.