Performance Analysis of Time Splitting Protocol in Multi-Femtocell Energy Harvesting Networks

This paper analyzes the performance of a two-tier heterogeneous network, where a macrocell is overlaid with several femtocells, each supporting users with limited energy resources. To enable sustainable uplink communication, femtocell users (FUs) harvest energy from their respective femtocell base stations (FBSs) using a time-switching (TS) protocol. Each time slot is divided into an energy harvesting phase and a bidirectional communication phase. Within each femtocell, multiple users are served in a time-division manner to avoid intracell interference, while inter-femtocell and macrocell interference are considered due to spectrum reuse. Closed-form expressions are derived for the outage probability and throughput under Rayleigh fading. Analytical and simulation results reveal a trade-off between energy harvesting duration and throughput, and show that performance saturates beyond a certain transmit power threshold. This work provides insights into the design of energy-efficient femtocell networks for next-generation green communication systems.