Joint DOA and DOD Estimation in a Wideband OFDM MIMO System

In this correspondence, a joint direction of departure (DOD) and direction of arrival (DOA) estimation method is proposed for a wideband multiple-input multiple-output (MIMO) system with orthogonal frequency division multiplexing (OFDM). In a wideband array system, the envelope-misalignment effect of signals on different array elements is unneglectable. To deal with this problem, the theoretical channel response of the wideband system for joint DOA and DOD estimation is given. Then, a coherent accumulation method to reconstruct a two-dimensional sinusoidal model following range compression is proposed, which simplifies the wideband array response to a narrow-band array representation. The range migration effect among transmit and receiving antenna pairs of the wideband array is eliminated. A theoretical deduction is present to prove the correctness of this method. The proposed algorithm is capable of sparsifying the dense targets, is highly computationally efficient, and is good at increasing the signal-tonoise ratio. The joint DOA and DOD estimation performance is also verified by numerical experiments