Spacing-Based Coupling Radiation Control in Pinching-Antennas Systems for Heterogeneous NOMA Users

TL;DR

This paper explores a novel spacing-based radiation control method in pinching-antenna systems to enhance semantic communication for heterogeneous NOMA users, optimizing spectral efficiency through an alternating optimization approach.

Contribution

It introduces a spacing-controlled adjustable radiation model in PASS for semantic communication, addressing the gap in flexible radiation control for heterogeneous users.

Findings

Proportional power PASS model achieves higher semantic spectral efficiency.

Spacing control improves interference management and QoS for heterogeneous users.

Simulation results outperform conventional schemes in various settings.

Abstract

Pinching-antennas systems (PASS) offer reconfigurable wireless channels via low-cost dielectric mediums by creating line-of-sight (LoS) communication links. Most of the existing PASS cover mechanisms of equal power pinching antennas for conventional bit-based communication, whereas flexible radiation control remains largely unexplored, particularly for heterogeneous semantic and bit users. In this paper, we investigate the performance of semantic communication (SC) using an adjustable radiation model over PASS, where the coupling strength between the dielectric waveguide and each pinching antenna is determined by the antenna-waveguide spacing. Specifically, the non-orthogonal multiple access (NOMA)-assisted heterogeneous users are served by multiple pinching antennas using spacing-controlled adjustable radiation ratios. Uunder this setting, we maximize the semantic spectral efficiency (SE) subject to the bit-user quality of service (QoS) requirement, successive interference cancellation (SIC) feasibility, and the minimum adjacent antennas spacing constraint. An alternating optimization (AO) approach optimizes users power allocation and positions of pinching antennas. Simulations demonstrate the effectiveness of the proportional power PASS model in providing higher semantic SE in different geometrical and numerical settings compared to conventional benchmark schemes.