Unitary dual-resolution ESPRIT for joint DOD and DOA estimation in bistatic MIMO radar

This paper investigates the problem of joint direction of departure (DOD) and direction of arrival (DOA) estimation in bistatic MIMO radar. A new bistatic MIMO array, both the transmit array and the receive array consist of two separated subarrays with dual baselines is proposed, in contrast to the modeling of both the transmit array and the receive array to be uniform linear array in the existing research literature. And a new joint DOD and DOA estimation algorithm, called unitary dual-resolution ESPRIT, is proposed. First, the short baseline rotational invariance within subarray yields non-ambiguous coarse DOD and DOA estimation. Then the long baseline rotational invariance between subarray yields high accuracy but cyclically ambiguous DOD and DOA estimation. Last, the combination of both estimates yield high accuracy and non-ambiguous DOD and DOA estimation. Moreover, we propose to utilize the properties of centro-Hermitian matrices to transform the complex-valued computations into real-valued computations throughout the whole process. The proposed algorithm gives significant improvement in DOD and DOA estimation performance, with automatic pairing and without extra antennas and computational complexity compared with the conventional algorithms. Simulation results verify the effectiveness of the proposed algorithm.