亚奈奎斯特采样雷达的运动目标回波信号的快速重构

亚奈奎斯特采样雷达是利用回波信号的稀疏性，基于模信转换系统发展起来的欠采样雷达系统.本文研究亚奈奎斯特采样雷达的运动目标回波信号的快速重构问题.与单脉冲回波重构不同，运动目标在脉冲积累时间内可能产生跨距离单元现象，使得回波信号表示系数呈现稀疏时变性.本文采用概率分布模型描述稀疏位置的变化，首先将多脉冲回波信号重构转化为加权稀疏重构问题；然后根据分段滑动重构思想，提出一种基于正交投影的加权稀疏分段滑动重构方法来实现快速重构.该方法利用前一个脉冲稀疏位置估计信息，构造分段产生干扰的正交补空间，将子段压缩测量投影到构造的正交补空间，有效地抑制了相邻段引入的干扰.数值仿真验证了方法的有效性.

Fast Reconstruction of Moving Target Echoes Based on Sub-Nyquist Radar

Sub-Nyquist radar is an analog-to-information based radar system with the assumption of sparse echo signals.We study the reconstruction of moving target echoes obtained from the sub-Nyquist radar.Different from the reconstruction of echo signals from a single pulse,the moving targets may be across range cells in a coherent processing interval and thus the echo signals have the property of the time-varying sparsity.However,it has been found that the sparse positions obey a probabilistic distribution and then a random model is adopted to describe the sparsity.The reconstruction of the multiple echoes is transformed into a weighted sparse reconstruction problem.An orthogonal-projection-based weighted sparse segment-sliding reconstruction (OP-WSegSR) scheme is proposed in this paper.Utilizing the estimation of sparse positions in the previous pulse,the scheme projects the measurements of the current segment onto the orthogonal complement subspace spanned by the interference generated in the segmentation process and then the adjacent interference is greatly rejected.Simulations show the effectiveness of the OP-WSegSR scheme.