Joint Beamforming and PD Orientation Design for Mobile Visible Light Communications

TL;DR

This paper introduces joint beamforming and PD orientation optimization for mobile VLC systems with adjustable receivers, addressing line-of-sight sensitivity and human blockage to improve QoS and reduce power consumption.

Contribution

It develops novel joint optimization algorithms for beamforming and PD orientation in mobile VLC, including robust methods for random UE orientations.

Findings

Joint optimization improves VLC QoS under various UE orientations.

Proposed algorithms effectively handle nonconvex optimization problems.

Numerical results demonstrate enhanced performance and power efficiency.

Abstract

In this paper, we propose joint beamforming and photo-detector (PD) orientation (BO) optimization schemes for mobile visible light communication (VLC) with the orientation adjustable receiver (OAR). Since VLC is sensitive to line-of-sight propagation, we first establish the OAR model and the human body blockage model for mobile VLC user equipment (UE). To guarantee the quality of service (QoS) of mobile VLC, we jointly optimize BO with minimal UE the power consumption for both fixed and random UE orientation cases. For the fixed UE orientation case, since the {transmit} beamforming and the PD orientation are mutually coupled, the joint BO optimization problem is nonconvex and intractable. To address this challenge, we propose an alternating optimization algorithm to obtain the transmit beamforming and the PD orientation. For the random UE orientation case, we further propose a robust alternating BO optimization algorithm to ensure the worst-case QoS requirement of the mobile UE. Finally, the performance of joint BO optimization design schemes are evaluated for mobile VLC through numerical experiments.