多输入多输出(MIMO)雷达作为一种新型的雷达体制,其成像兼具高分辨率与实时性的优点。由于观测区域的稀疏性,MIMO雷达成像可以用压缩感知的方法进行处理。而现有的MIMO雷达稀疏成像的贪婪恢复算法中,正交匹配追踪算法(OMP)存在成像图像有伪影的缺点,子空间追踪算法(SP)则受到低分辨率的困扰。针对上述问题,该文提出一种称为混合匹配追踪算法的压缩感知贪婪算法以实现MIMO雷达稀疏成像。通过将两种贪婪恢复算法结合起来,利用OMP算法选择基信号的正交性和SP算法具有基信号选择的回溯策略,来重构出高分辨率且没有伪影的雷达图像。仿真实验验证了所提算法的有效性。
MIMO radar is an emerging radar system that has significant potential. MIMO radar can provide high resolution and real-time imaging solution. Because of the sparsity of the observation zone, the task of MIMO radar imaging can be formulated as a problem of sparse signal recovery based on Compressed Sensing (CS). In MIMO radar imaging application based on CS, existing greedy algorithms, such as the Orthogonal Matching Pursuit (OMP) algorithm and the Subspace Pursuit (SP) algorithm, suffer from artifacts and low-resolution, respectively. To deal with the drawback of existing greedy algorithms, a Hybrid Matching Pursuit (HMP) algorithm is proposed to combine the strengths of OMP and SP. By using of the orthogonality among selected basis-signals and the backtracking strategy for basis-signal reevaluation, the HMP algorithm can reconstruct high-resolution radar image with no artifacts. Simulation results demonstrate the effectiveness and superiority of the proposed algorithm.