DOA Estimation via an Augmented Unfolded Coprime MIMO Configuration of Transceiver Reversal with Enhanced Degrees of Freedom

This paper proposes an augmented unfolded coprime MIMO configuration of transceiver reversal, where the transmitter adopts an augmented unfolded coprime array, and the layout of the receiver is obtained by flipping the transmitter. From the perspective of the sum-difference co-array (SDCA), the closed-form expressions for the range of consecutive lags, the number of discrete lags and the degrees of freedom (DOF) are derived. Moreover, the sparse reconstruction method of interpolated virtual elements is employed for direction of arrival (DOA) estimation. Compared with the conventional coprime MIMO configuration, the proposed MIMO can provide more DOF and larger virtual aperture. Simulation results verify the superior performance of the proposed MIMO configuration.