Beamforming Design With Partial Group Successive Interference Cancelation for ISAC Systems

Mengqiu Chai, Shengjie Zhao, Fengxia Han, Yuan Liu

Abstract: Integrated sensing and communication (ISAC) is an emerging paradigm in the sixth-generation mobile communication systems (6G) to address the spectrum scarcity and realize the vision of the Internet of Everything (IoE). In this article, we consider a multiple-input-multiple-output (MIMO) ISAC system where the dual-functional radar-communication (DFRC) base station (BS) detects the targets and communicates with multiple downlink users. To meliorate the severe interference management and improve the transmission performance of the ISAC system, we identify a specific transceiver design that splits each independent message into multiple layers at the transmitter and employs a partial group successive interference cancelation scheme at the receivers. To coordinate the communication and radar performance, we formulate an optimization problem to approximate the beamformers to the desired radar beampattern subject to the achievable rate regions. Since, the formulated problem is nonconvex and NP-hard, we propose an iterative algorithm based on the semi-definite programming relaxation, which optimizes the beamformers and rate vectors alternatively to yield near-optimal solutions. Numerical results demonstrate the superior performance of the proposed transceiver design in improving the achievable transmission rate and obtaining better interference management in the ISAC system.