Jointly Correlated Dual-Side Fluid Antenna System

TL;DR

This paper analyzes the ergodic capacity of a dual-side fluid antenna system with joint correlation, deriving a closed-form upper bound and proposing an optimal power allocation algorithm.

Contribution

It introduces a joint correlation channel model for dual-side FAS and provides a capacity analysis with a practical power allocation method.

Findings

Derived a tight closed-form upper bound for ergodic capacity.

Developed a joint correlation channel model for dual-side FAS.

Proposed an iterative algorithm for optimal power allocation.

Abstract

Fluid antenna systems (FASs) have introduced a new paradigm for wireless system design by revealing how mutual correlation can be exploited to harvest inherent spatial diversity. While existing studies have mainly focused on one-sided FAS configurations, i.e., with FAS deployed at either the transmitter or the receiver, this work investigates the ergodic capacity of a jointly correlated dual-side FAS under statistical eigenmode transmission. Specifically, a jointly correlated dual-side channel model is developed, and the corresponding ergodic capacity together with a tight closed-form upper bound is derived. In addition, the optimal power allocation is studied, and a practical iterative algorithm is proposed for its implementation.