Joint Relay Beamforming and Waveform Design for Dual-Functional Radar and Relaying Networks

To obtain precise sensing data for achieving wireless network intelligence within the confines of the limited available spectrum, there has been an increasing interest in dual-functional radar and communication. This letter focuses on a dual-functional radar and relaying system, where the half-duplex amplify-and-forward radar-enabled relay (RR) needs to assist the source node (SN) in transmitting information to the destination node while simultaneously tracking radar targets in several desired directions. To balance the performance of sensing and communication, we propose to minimize the beampattern matching error by optimizing the relay beamforming and waveform design, subject to the maximum transmit power at the RR and the minimum transmission rate at the SN. To solve the formulated non-convex problem, after reformulating the problem with the Schur complement lemma, a majorization minimization-based local optimal method is proposed. Simulation results indicate that the method we proposed exhibits superior performance when compared to the benchmark schemes.