Analyzing Optical TDMA to Mitigate Interference in Downlink LiFi Optical Attocell Networks

TL;DR

This paper analyzes the use of TDMA in downlink LiFi attocell networks to mitigate interference, deriving an exact expression for goodput and demonstrating optimal scheduling to enhance network performance.

Contribution

It provides a novel interference characterization and optimal TDMA scheduling strategy for LiFi attocell networks with a detailed analytical framework.

Findings

TDMA scheduling significantly reduces interference.

Optimal LED scheduling maximizes network goodput.

Analytical expression for goodput in a square lattice network.

Abstract

Co-channel interference in the downlink of LiFi attocell networks significantly decreases the network performance in terms of rate. Analysis of multiple access schemes is essential to mitigate interference and improve rate. The light emitting diodes (LEDs) being centrally monitored, the time division multiple access (TDMA) scheme over the LEDs will be suitable to analyze. This work considers the interference characterization in [1] over M-PAM modulated signals to derive an exact expression for the goodput G of the time scheduled attocell network, which is arranged as a deterministic square lattice in two dimensions. Given this TDMA over the LEDs, numerical simulations show that the LEDs can be optimally time scheduled to maximize the goodput, which implies that the TDMA mitigates interference in an attocell network compared to the case when the LEDs are unscheduled.