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arXiv · 2508.14753

Full-Duplex Beamforming Optimization for Near-Field ISAC

Ahsan Nazar·Zhambyl Shaikhanov·Sennur Ulukus
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Abstract

Integrated Sensing and Communications (ISAC) is a promising technology for future wireless networks, enabling simultaneous communication and sensing using shared resources. This paper investigates the performance of full-duplex (FD) communication in near-field ISAC systems, where spherical-wave propagation introduces unique beam-focusing capabilities. We propose a joint optimization framework for transmit and receive beamforming at the base station to minimize transmit power while satisfying rate constraints for multi-user downlink transmission, multi-user uplink reception, and multi-target sensing. Our approach employs alternating optimization combined with semidefinite relaxation and Rayleigh quotient techniques to address the non-convexity of the problem. Simulation results demonstrate that FD-enabled near-field ISAC achieves superior power efficiency compared to half-duplex and far-field benchmarks, effectively detecting targets at identical angles while meeting communication requirements.

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Ahsan Nazar, Zhambyl Shaikhanov, Sennur Ulukus. 2025-08-20. Full-Duplex Beamforming Optimization for Near-Field ISAC. https://arxiv.org/abs/2508.14753

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