Waveform Design for Multi-Carrier Multiuser MIMO Joint Communications and Sensing

We consider a joint communications and sensing (JCAS) system that operates as a monostatic MIMO radar while simultaneously providing downlink communications service to multiple single-antenna users. We address the joint optimization of transmit waveform design and subcarrier allocation. Specifically, we focus on maximizing the minimum radar signal-to-interference-plus-noise ratio (SINR) while ensuring communications SINR and power constraints. To tackle this challenging problem, we decompose it into two subproblems by using alternating optimization. Subsequently, we employ a successive convex approximation (SCA) algorithm to find an effective solution for the resulting nonconvex waveform design problem. The numerical results indicate that the proposed method converges and show the tradeoff between radar and communications performances.