Joint estimation of DOD and DOA for bistatic MIMO assisted by Intelligent Reflecting Surface

Abstract

Intelligent Reflecting Surface (IRS) represents a significant breakthrough in wireless communication. It can reconstruct wireless channels even when there are obstructions between the transmitting array (Tx) and the receiving array (Rx), enabling Multiple-Input Multiple-Output (MIMO) radar to locate targets from non-line-of-sight (NLOS) directions, however, existing optimization-based methods are too complex to be practically implemented. This paper investigates the angle estimation problem for arbitrary manifold array bistatic MIMO radar and proposes a joint two-dimensional direction-of-departure (2D-DOD) and two-dimensional direction-of-arrival (2D-DOA) estimation algorithm assisted by an IRS. The algorithm employs the PM algorithm and the spectral peak search method to estimate direction-of-departure (DOD) and direction-of-arrival (DOA), respectively, achieving a four-dimensional angle estimation. The proposed framework can jointly estimate two-dimensional NLOS signals without the need to pre-understand the target-IRS channel, the algorithm’s complexity and angle estimation error are analyzed, and simulation results confirm both the efficacy and superiority of the proposed algorithm.