A SIMO Hybrid Visible Light Communication System for Optical IoT

Abstract

Visible light communications (VLC) is an emerging technology utilizing light emitting diodes and photodetectors (PDs) and cameras (i.e., image sensors (ISs)) as the transmitter and receivers (Rx), respectively for simultaneous data communications, illumination, localization and sensing in indoor optical Internet of Things. We propose, a single-input multipleoutput (SIMO) hybrid VLC system using PD-and IS-based Rxs for simultaneous high-and low-speed (i.e., Rb-High and Rb-Low) data transmission. In addition, we propose amplitude overlapping AOL in the modulation format to increase the Rb and reduce the attenuation due to high-pass filter effect of the bias-T. We experimentally evaluate the performance of the proposed scheme considering the inter-link impacts. Results show that, at AOL of 0 -0.2, (i) the measured bit error rate for the PD-based VLC is below the forward error correction limit of 3.8×10-3 for Rb-Low of 2.5 and 5 kb/s at Rb-High of 35 and 60 Mb/s, respectively; and (ii) for the ISbased VLC link with the camera gain of 4 dB and Rb-High of up to 70 Mb/s, the reception success rates are > 96 and 90% at Rb-Low of 2.5 and 5kb/s, respectively.