Em-based sparse imaging for colocated MIMO radar under phase synchronization mismatch

Multiple-input multiple-output (MIMO) radar with colocated antennas is expected to achieve good imaging performance via coherent processing. However, a crucial factor to this process-phase synchronization, which directly determines the performance gain, has rarely been studied in previous works. Hence in this paper, given the sparsity of the target, we address the problem of imaging for colocated MIMO radar under the phase synchronization mismatch. Based on the model assumption that the phase synchronization mismatch in each propagation path is an independent and identically distributed uniform random variable, we combine the sparsity of the target and expectation maximization (EM) method to develop an EM-based sparse imaging algorithm against such random phase mismatch. The effectiveness of the proposed algorithm is demonstrated by numerical simulations.