Sum-rate Optimization for Radar and Communication Coexistence

Radar-communication coexistence is a promising way to deal with limited spectrum resource. In this paper, we discuss the coexistence between a multiple-input-multiple-output (MIMO) communication system and a MIMO radar. For a given requirement of the interference power from communication to radar, beamforming optimization problems which maximize the communication sum-rate are formulated, transformed into convex and solved. Besides beamforming optimization for perfect channel estimation, a robust beamforming approach is proposed for imperfect channel estimation. Numerical results prove that the proposed beamforming approaches promote the coexistence between communication and radar and also illustrate the trade-off between the performance of the two systems.