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arXiv · 2510.03628

Pinching Antenna Systems (PASS) for Cell-Free Communications

Haochen Li·Jiayi Lei·Cheng Zeng·Zhaoming Hu·Chao Dong·Yuanwei Liu
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Abstract

A pinching antenna system (PASS) assisted cell-free communication system is proposed. A sum rate maximization problem under the BS power budget constraint and PA deployment constraint is formulated. To tackle the proposed non-convex optimization problem, an alternating optimization (AO) algorithm is developed. In particular, the digital beamforming sub-problem is solved using the weighted minimum mean square error (WMMSE) method, whereas the pinching beamforming sub-problem is handled via a penalty based approach combined with element-wise optimization. Simulation results demonstrate that: 1) the PASS assisted cell-free systems achieve superior performance over benchmark schemes; 2) increasing the number of PAs per waveguides can improve the advantage of PASS assisted cell-free systems; and 3) the cell-free architecture mitigates the average user rate degradation as the number of users increases.

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Haochen Li, Jiayi Lei, Cheng Zeng, Zhaoming Hu, Chao Dong, Yuanwei Liu. 2025-10-04. Pinching Antenna Systems (PASS) for Cell-Free Communications. https://arxiv.org/abs/2510.03628

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