Rate-Splitting Multiple Access for Dual-Functional Radar-Communication Satellite Systems

• Published in: IEEE Wireless Communications and Networking Conference : [proceedings] : WCNC pp. 1 - 6
• Main Authors: Yin, Longfei, Clerckx, Bruno
• Format: Conference Proceeding
• Language: English
• Published: IEEE 10.04.2022
• Subjects: Array signal processing; beamforming; bistatic MIMO radar; Cramér-Rao bound; dual-functional radar-communication (DFRC); Estimation; multibeam satellite systems; Parameter estimation; Quality of service; Rate-splitting multiple access (RSMA); Satellites; Simulation; Spaceborne radar
• ISSN: 1558-2612
• DOI: 10.1109/WCNC51071.2022.9771644

In this paper, we consider a multi-antenna dual-functional radar-communication (DFRC) satellite system, where the satellite has a dual capability to simultaneously communicate with downlink satellite users (SUs) and probe detection signals to a moving target. To design an appropriate DFRC waveform, we investigate the rate-splitting multiple access (RSMA)-assisted DFRC beamfoming, and employ the Cramér-Rao bound (CRB) as a radar performance metric, which represents a lower bound on the variance of unbiased estimators. The beamforming is optimized to minimize the CRB subject to quality of service (QoS) constraints of SUs and a per-feed transmit power budget. Satellite communication and detecting ground/ sea objects in a bistatic mode are accomplished simultaneously using the DFRC waveform we designed. Simulation results demonstrate that the proposed RSMA-assisted DFRC beamforming outperforms the conventional space-division multiple access (SDMA) strategy in terms of the communication-sensing trade-off and target estimation performance in a multibeam satellite system.