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arXiv · 2104.08180

Rate-Splitting Multiple Access for Joint Radar-Communications with Low-Resolution DACs

Onur Dizdar·Aryan Kaushik·Bruno Clerckx·Christos Masouros
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Abstract

In this paper, we introduce the design of a multi-antenna Joint Radar-Communication (JRC) system with Rate Splitting Multiple Access (RSMA) and low resolution Digital-to-Analog Converter (DAC) units. Using RSMA, the communication messages are split into private and common parts, then precoded and quantized before transmission. We use a problem formulation to design the JRC system with RSMA and low resolution DACs by maximizing communication sum-rate and the proximity of the resulting JRC waveform to an optimal radar beampattern under an average transmit power constraint. We solve the joint sum-rate maximization and beampattern error minimization problem using Alternating Direction Method of Multipliers (ADMM) method. The numerical results show that RSMA achieves a significantly higher sum-rate compared to Space Division Multiple Access (SDMA) while providing the same Normalized Mean Square Error (NMSE) for the designed radar beampattern.

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Onur Dizdar, Aryan Kaushik, Bruno Clerckx, Christos Masouros. 2021-04-16. Rate-Splitting Multiple Access for Joint Radar-Communications with Low-Resolution DACs. https://arxiv.org/abs/2104.08180

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