A Public Information Precoding for MIMO Visible Light Communication System Based on Manifold Optimization

TL;DR

This paper introduces a manifold optimization-based precoding method for MIMO-VLC systems to enhance public information transmission, achieving higher power efficiency and improved signal quality compared to traditional methods.

Contribution

It proposes a novel omnidirectional precoding technique for MIMO-VLC systems using manifold optimization to maximize achievable rate and power efficiency.

Findings

Achieves higher received mean power and better bit error rate.

Outperforms classical precoding methods without precoding.

Demonstrates effectiveness through simulation results.

Abstract

Visible light communication (VLC) is an attractive subset of optical communication that provides a high data rate in the access layer of the network. The combination of multiple inputmultiple output (MIMO) with a VLC system leads to a higher speed of data transmission named as MIMO-VLC system. In multi-user (MU) MIMO-VLC, a LED array transmits signals for users. These signals are categorized as signals of private information for each user and signals of public information for all users. The main idea of this paper is to design an omnidirectional precoding to transmit the signals of public information in the MUMIMO-VLC network. To this end, we propose to maximize the achievable rate which leads to maximizing the received mean power at the possible location of the users. Besides maximizing the achievable rate, we consider equal mean transmission power constraint in all LEDs to achieve higher power efficiency of the power amplifiers used in the LED array. Based on this we formulate an optimization problem in which the constraint is in the form of a manifold and utilize a gradient method projected on the manifold to solve the problem. Simulation results indicate that the proposed omnidirectional precoding can achieve superior received mean power and bit error rate with respect to the classical form without precoding utilization.