超宽带穿墙雷达高效的TV-MAP稀疏成像方法

现有的穿墙雷达稀疏成像方法中构建的字典矩阵占据存储空间大，而且计算复杂度高，成像时间长。为此，本文针对全变分（TV）约束的最大后验（MAP， TV-MAP）稀疏成像方法，利用超宽带窄脉冲波形的特点和冲激函数具有的抽样特性，将优化最小化（MM）框架下的交替迭代更新公式中包含字典矩阵的相关运算用线性卷积和哈希表代替，避免了字典矩阵的构造、存储与计算；同时，通过对发射序列进行变换，使所提方法可以适用于任何超宽带发射波形，而不限于对称的发射波。仿真和实验结果表明，该方法不仅减少了所需内存，降低了时间复杂度，而且有效地抑制了杂波。

Efficient TV-MAP Sparse Imaging Method for Ultra-Wideband Through-the-Wall Radar

The dictionary matrix constructed in the existing through-the-wall radar sparse imaging methods needs a large storage space. Moreover, these methods have high computational complexity and long imaging time. By means of the characteristics of ultra-wideband narrow pulse waveform and the sampling characteristics of impulse function, this paper uses linear convolution and Hash table to replace the related operations including the dictionary matrix in the alternative and iterative updating formula of the maximum a posteriori (MAP) sparse imaging method with total variation (TV) constraint under the framework of majorize-minimize (MM). In this way, the construction, storage and calculation of dictionary matrix are avoided. At the same time, by transforming the transmission sequence, this method can be applied to any ultra-wideband transmission waveform, not limited to symmetrical one. The simulation and experimental results show that the proposed method not only reduces the required memory and time complexity, but also effectively suppresses the clutter.