Delta-Sigma Modulated Visible Light Communication Illumination System Using a Projector with the Digital Micro-Mirror Device.

Motoi Kodama,Shinichiro Haruyama

doi:10.3390/s19245512

Abstract

There is a unique transmission method of visible light communication (VLC) that can transmit multiple data in multiple directions simultaneously by using a projector with the digital micro-mirror device (DMD). Previously, we proposed a method of transmitting data from the projector that transmits digitally modulated VLC signal from each pixel, and in this paper, we propose an extension of the method to transmit audio signal by using a special type of modulation called delta-sigma-modulation (DSM). The DSM-VLC system employs a simple receiver that comprises simple analog electric circuits, which contribute to low power consumption. We made a DSM-VLC prototype and verified that the prototype was able to send four different waves to different directions. Additionally, the experiments’ results agree very well with the simulation results. Furthermore, we designed two types of DSM: pulse width modulation (PWM) and pulse density modulation (PDM), and we verified that the PDM-VLC is better than the PWM-VLC regarding the DMD switching frequency’s efficiency. Our proposed DSM-VLC can be used for such applications as voice information guidance systems with direction-selective messages.

Highlights

Visible light communication (VLC) is an optical wireless communication technique that utilizes the light visible to humans [1,2]
We proposed the delta-sigma modulator (DSM)-VLC, including the pulse width modulation (PWM)-VLC and the pulse density modulation (PDM)-VLC, using a
We proposed the delta-sigma-modulated VLC (DSM-VLC), including the pulse width-modulated VLC (PWM-VLC) and the pulse density-modulated VLC (PDM-VLC), using a projector with the digital micro-mirror device (DMD) as the voice information guidance system, and we reported the fundamental projector with the DMD as the voice information guidance system, and we reported the fundamental simulations and experiments conducted

Summary

Introduction

Visible light communication (VLC) is an optical wireless communication technique that utilizes the light visible to humans [1,2]. The projector VLC (PVLC) has been studied to achieve the novel displays emitting imperceptible metadata along with the image [10,11,12,13,14,15]. Kimura et al developed EmiTable [12], which is a tabletop surface pervaded with imperceptible metadata, whereas Kato et al developed iPvlc [13], which is pixel-level PVLC. In these previously conducted studies, a projector with the digital micro-mirror device (DMD) could not be applied for the location service technology. According to reference [25],described in Z-domain model demonstrated, the relational expression. According to reference [25],described in Z-domain model demonstrated in Figure 4, the relational expression

Objectives

Results

Conclusion