Rate-Splitting Multiple Access for Multi-Antenna Joint Radar and Communications

Dual-Functional Radar-Communication (DFRC) system is an essential and promising technique for beyond 5G. In this work, we propose a powerful unified multi-antenna DFRC transmission framework, where additional radar sequence transmitted apart from communication streams to enhance beampattern matching capability, Rate-Splitting Multiple Access (RSMA) adopted better manage the interference. RSMA relies on (RS) with Successive Interference Cancellation (SIC) receivers, split encoding of messages into common private streams. We design message precoders jointly maximize Weighted Sum Rate (WSR) minimize approximation Mean Square Error (MSE) subject per antenna power constraint. An iterative algorithm based Alternating Direction Method Multipliers (ADMM) developed solve problem. Numerical results first show that RSMA-assisted achieves tradeoff between WSR than Space-Division (SDMA)-assisted or without sequence, other simpler radar-communication strategies using orthogonal resources. also frameworks achieve same performance. This because stream exploited in proposed framework. The fulfils triple function managing interference among users, radar, approximation. Therefore, by enabling DFRC, performance enhanced while architecture simplified since there no need use SIC. conclude more multiple access DFRC.