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arXiv · 2609.31088

Impact of Antenna Position Errors on TDMA and NOMA in Pinching-Antenna Systems

Wei Jiang·Hans D. Schotten
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Abstract

Pinching-antenna systems (PASS) create reconfigurable wireless channels by moving dielectric antennas along a waveguide. Mechanical position errors translate into phase errors that degrade performance, yet almost all prior PASS studies assume ideal placement. This paper models this position error, derives the resulting phase error, and analyzes its impact on time-division multiple access (TDMA) and non-orthogonal multiple access (NOMA), obtaining their ergodic-rate bounds and closed-form outage probabilities. Analyses and simulations reveal that single-antenna TDMA is immune to position error, whereas multi-antenna TDMA loses array gain and NOMA suffers an interference floor that cannot be overcome by increasing transmit power.

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Wei Jiang, Hans D. Schotten. 2026-09-25. Impact of Antenna Position Errors on TDMA and NOMA in Pinching-Antenna Systems. https://arxiv.org/abs/2609.31088

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