Breaking the Barriers: An Active RIS-Enhanced DFRC System for Improved Multi-User Communication
Ravi A Patel, Keshav K. Singh, Shahid Mumtaz, Sudip Biswas · 2024
As we advance towards sixth-generation (6G) communications, the integration of dual-functional radar and communication (DFRC) systems with active reconfigurable intelligent surfaces (RIS) emerges as a promising solution to enhance spectrum efficiency. This work introduces an innovative DFRC system enhanced by an active RIS, capable of amplifying and phase-shifting signals to improve communication quality. We propose an optimization algorithm that maximizes combined data rates while considering constraints on radar probing power and power budgets for both DFRC and active RIS. Employing techniques such as weighted minimum mean square error (WMMSE) and fractional programming, our simulation results demonstrate that active RIS-enhanced DFRC systems significantly outperform passive RIS and non-RIS setups in terms of Weighted Sum Rate (WSR). Further analyses reveal that active RIS effectively mitigates multiplicative fading and enhances signal directivity, with performance gains influenced by the number of RIS elements, total system power, and radar detection power ratio. This work highlights the transformative potential of active RIS in optimizing next-generation wireless networks.