Low-complexity Transceiver Beamforming for DFRC with MIMO Radar and MU-MIMO Communication

Spatial beamforming is an efficient way to realize dual-functional radar-communication (DFRC) for integrated sensing and communications towards 6G network. In this paper, we study the DFRC design for a general scenario, where the dual-functional base station simultaneously detects the target as a MIMO radar while communicating with multiple multi-antenna communication users (CUs). This necessitates a joint transceiver beamforming design for both MIMO radar and multi-user MIMO communication. In order to avoid iterative optimization with high complexity, two low-complexity beamforming designs based on CU-selection and zero-forcing are proposed, where the closed-form expressions of the low-complexity beamforming designs are derived. Simulation results are provided to verify the effectiveness of the proposed low-complexity designs.