On Optimizing Rate Splitting in Laser-based Optical Wireless Networks

TL;DR

This paper explores advanced interference management techniques in laser-based optical wireless networks, proposing hierarchical rate splitting and optimized power allocation to significantly improve data rates in high-density environments.

Contribution

It introduces hierarchical rate splitting with an outer common message and formulates an optimization problem for power allocation to enhance network performance.

Findings

HRS outperforms conventional RS in high-density scenarios.

Optimized power allocation improves achievable rates.

Proposed methods effectively manage inter-user and inter-group interference.

Abstract

Optical wireless communication (OWC) is a promising technology that has the potential to provide Tb/s aggregate rates. In this paper, interference management is studied in a Laser-based optical wireless network where vertical-cavity surface-emitting (VCSEL) lasers are used for data transmission. In particular, rate splitting (RS) and hierarchical rate splitting (HRS) are proposed to align multi-user interference, while maximizing the multiplexing gain of the network. Basically, RS serves multiple users simultaneously by splitting a message of a user into common and private messages, each message with a certain level of power, while on the other side users decode their messages following a specific methodology. The performance of the conventional RS scheme is limited in high density wireless networks. Therefore, the HRS scheme is developed aiming to achieve high rates where users are divided into multiple groups, and a new message called outer common message is used for managing inter-group interference. We formulate an optimization problem that addresses power allocation among the messages of the HRS scheme to further enhance the performance of the network. The results show that the proposed approach provides high achievable rates compared with the conventional RS and HRS schemes in different scenarios.