Pinching Antenna-Assisted ISAC with Waveguide Mode Selection

2026-07-16

AI Summary

This work addresses the limited spatial degrees of freedom in existing integrated sensing and communication (ISAC) systems with fixed receive antenna positions or predetermined waveguide modes. To overcome this limitation, the paper proposes a reconfigurable waveguide-mode ISAC architecture that jointly optimizes waveguide mode selection, transmit beamforming, and transceiver antenna placement to maximize the sensing signal-to-noise-plus-clutter ratio under multi-user communication quality-of-service constraints. The study introduces, for the first time, a reconfigurable waveguide mode mechanism that enables coordinated scheduling of communication and sensing resources, significantly enhancing sensing robustness in demanding communication scenarios. An efficient solution to the resulting mixed-integer nonconvex problem is developed using a penalty-based block coordinate descent algorithm combined with majorization–minimization techniques. Simulations demonstrate that the proposed scheme substantially outperforms conventional designs with fixed antennas or fixed modes, validating the synergistic gains of spatial adaptability and mode reconfigurability.

Abstract

Conventional pinching antenna (PA)-assisted integrated sensing and communication (ISAC) architectures typically assume static receiver locations or predetermined receive waveguides, thereby underutilizing the inherent spatial degrees of freedom. This paper proposes a novel mode-selectable PA-assisted ISAC framework to maximize the post-combining sensing signal-to-noise ratio while satisfying multi-user quality-of-service constraints by jointly optimizing the waveguide mode selection, transmit beamforming, and transmit/receive PA positions. To tackle the resulting mixed-integer nonconvex optimization problem, we develop a low-complexity block-coordinate descent algorithm that leverages a penalty-based majorization-minimization method to achieve high-quality suboptimal solutions. Numerical results demonstrate that the proposed design significantly outperforms both traditional PA and fixed-antenna benchmarks by synergistically harnessing spatial adaptability and modal reconfigurability. In particular, the mode-selectable design enables the coordinated optimization of transmit/receive operations and sensing-communication resource allocation, thereby maintaining sensing robustness under stringent communication requirements.

Problem

• Integrated Sensing and Communication
• Pinching Antenna
• Waveguide Mode Selection
• Spatial Degrees of Freedom
• Multi-user QoS

Innovation

• mode selection
• pinching antenna
• integrated sensing and communication
• spatial adaptability
• beamforming optimization