LED Half-Power Angle Optimization for Ultra-Dense Indoor Visible Light Communication Network Deployment

Jiaojiao Xu,Zhengyuan Xu,Jianghua Luo,Chen Gong

doi:10.1109/ojcoms.2020.3005421

Abstract

Due to limited interference range, the advantage of visible light communication (VLC) over wireless fidelity (WiFi) lies more in the unit-area transmission rate rather than the single-link transmission rate. To characterize the achievable transmission rate per unit area, we consider an indoor downlink VLC network with dense attocell configuration for the transmitters with single-color light-emitting diode (LED) and multi-color LEDs, assuming binomial distributed users. We divide each attocell into central region and boundary region, and propose the transmission protocols based on such attocell division. We optimize the LED half-power angle to maximize the mean achievable transmission rate per unit area. More specifically, we investigate the rates of cell-center and cell-boundary users under fairness consideration for the single LED transmitter system. We characterize the mean achievable transmission rate per unit area under the white light constraints in the multiple LEDs transmitter system. The performance of the proposed transmission protocols is evaluated by numerical results.

Highlights

F UTURE wireless communication will expand the spectrum to higher frequency region to meet the demand for massive access and high communication rates
The default system parameters of single light-emitting diode (LED) transmitter for the indoor visible light communication (VLC) attocell communication system are listed in Table 1, including the room size, the transmitting LED
The white light illumination constraint leads to different optical transmission power of the R/G/B LED placed at the center

Summary

Introduction

F UTURE wireless communication will expand the spectrum to higher frequency region to meet the demand for massive access and high communication rates. In a typical visible light communication (VLC) system, low-cost LEDs and photodiodes (PDs) are widely employed for the transmitter and the receiver, respectively [5]. Compared with other communication methods, VLC can potentially offer high modulation bandwidth with pre-/post-equalizers, high transmission rate, and enhanced security. It is attracting extensive research interests from both academia and industrial areas [6]–[9]. Due to limited transmission range and interference range, one advantage of VLC lies in the deployment of dense attocells [10]–[12], where the mean unit-area achievable transmission rate can be significantly enhanced, at the cost of more complicated network infrastructure. Work [10] presents an analytical model for the coverage analysis of multiuser VLC networks considering the cooperation among access

Objectives

Results

Conclusion