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arXiv · 2604.04589

Greedy and Transformer-Based Multi-Port Selection for Slow Fluid Antenna Multiple Access

Darian Perez-Adan·Jose P. Gonzalez-Coma·F. Javier Lopez-Martinez·Luis Castedo
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Abstract

We address the port-selection problem in fluid antenna multiple access (FAMA) systems with multi-port fluid antenna (FA) receivers. Existing methods either achieve near-optimal spectral efficiency (SE) at prohibitive computational cost or sacrifice significant performance for lower complexity. We propose two complementary strategies: (i) GFwd+S, a greedy forward-selection method with swap refinement that consistently outperforms state-of-the-art reference schemes in terms of SE, and (ii) a Transformer-based neural network trained via imitation learning followed by a Reinforce policy-gradient stage, which approaches GFwd+S performance at lower computational cost.

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Darian Perez-Adan, Jose P. Gonzalez-Coma, F. Javier Lopez-Martinez, Luis Castedo. 2026-04-06. Greedy and Transformer-Based Multi-Port Selection for Slow Fluid Antenna Multiple Access. https://arxiv.org/abs/2604.04589

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