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arXiv · 2506.13490

Pinching-Antenna Systems (PASS) Meet Multiple Access: NOMA or OMA?

Qiao Ren·Xidong Mu·Siyu Lin·Yuanwei Liu
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Abstract

A fundamental two-user PASS-based communication system is considered under three MA schemes, namely non-orthogonal multiple access (NOMA), frequency division multiple access (FDMA), and time division multiple access (TDMA). For each MA scheme, a pinching beamforming optimization problem is formulated to minimize the required transmit power for satisfying users' rate requirements. For NOMA and FDMA, a two-stage algorithm is proposed, where the locations of PAs are derived sequentially by using the successive convex approximation (SCA) method and fine-turning phase adjustment. For TDMA, by leveraging the time-switching feature of PASS, the optimal pinching beamforming of each time slot is derived to maximize the served user channel gain. Numerical results are provided to show that: 1) PASS can achieve a significant performance gain over conventional antenna systems, and 2) NOMA consistently outperforms FDMA, while TDMA provides superior performance than NOMA for symmetric user rate requirements.

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Qiao Ren, Xidong Mu, Siyu Lin, Yuanwei Liu. 2025-06-16. Pinching-Antenna Systems (PASS) Meet Multiple Access: NOMA or OMA?. https://arxiv.org/abs/2506.13490

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