Energy Efficiency Maximization for Fluid Antenna-Enabled Interference-Limited Wireless Sensor Networks

Abstract

This letter investigates the energy efficiency (EE) of a fluid antenna-enabled clustered uplink wireless sensor network under co-channel interference. A reference sensor cluster is served by a fluid antenna-enabled access point, while neighboring clusters reuse the same uplink resource and generate interference. The AP selects the receive port that maximizes the interference-aware signal-to-interference-plus-noise ratio (SINR) coefficient, and the sensor transmit powers are optimized to maximize EE. For fixed port selection, a closed-form power control solution is derived using fractional programming. A correlation-aware scaling analysis based on an effective independent-port approximation is also provided to explain the EE saturation caused by spatial correlation. Numerical results show that the proposed scheme outperforms benchmark schemes, especially in interference-limited regimes.