Compressive Sensing-Based Two-Step Multipath Suppression Method for MIMO Through-the-Wall Radar Imaging

In this paper, we consider the problem of multipath suppression for through-the-wall radar imaging (TWRI). Exploiting the spatial diversity characteristic of multiple-input-multiple-output (MIMO) radar, we present a novel framework integrated compressive sensing and spatial filtering to formulate a ghost-free image with high-resolution. Specifically, an array signal processing model that accounts for the direction of departure (DoD), direction of arrival (DoA) and time of arrival (ToA) is established, where the signal with unequal DoD and DoA is regarded as the multipath. For the purpose of computational efficiency, we present a two-step method to solve the proposed large-scale problem, where the alternating direction method of multiplier (ADMM) and Capon beamforming are employed. Finally, the performance of the proposed method is verified via simulations.