Performance Analysis of Slow Fluid Antenna Multiple Access in Noisy Channels Using Gauss-Laguerre and Gauss-Hermite Quadratures

Fluid antenna system (FAS) facilitating a position-switchable antenna, enables a mobile receiver to exploit the deep fade opportunity of its interference for multiple access. Slow fluid antenna multiple access (
$s$
-FAMA) is such an emerging proposal that lets multiple users share the same time-frequency channel while each user adopts a fluid antenna to resolve the interference. Previous performance analysis is limited to the case when noise is neglected. In this letter, we remove this limitation and derive new closed-form expressions for the outage probability of
$s$
-FAMA by using Gauss-Laguerre and Gauss-Hermite Quadratures. The analysis reveals the impact of noise on the outage probability for different numbers of users and ports in
$s$
-FAMA networks.