A SIMO Hybrid Visible-Light Communication System for Optical IoT

Visible-light communication (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 the indoor optical Internet of Things. We propose a single-input–multiple-output (SIMO) hybrid VLC system using PD-based and IS-based Rxs for simultaneous high-speed and low-speed (i.e.,
$R_{b-{\mathrm{ High}}}$
and
$R_{b-{\mathrm{ Low}}}$
) data transmission. In addition, we propose amplitude overlapping
${A} _{\mathrm{ OL}}$
in the modulation format to increase
$R_{b}$
and reduce the attenuation due to the high-pass filter effect of the bias-T. We experimentally evaluate the performance of the proposed scheme considering the interlink impacts. Results show that at
${A} _{\mathrm{ OL}}$
of 0–0.2: 1) the measured bit error rate for the PD-based VLC is below the forward error correction limit of
$3.8 \times 10^{-3}$
for
$R_{b-{\mathrm{ Low}}}$
of 2.5 and 5 kb/s at
$R_{b-{\mathrm{ High}}}$
of 35 and 60 Mb/s, respectively, and 2) for the IS-based VLC link with the camera gain of 4 dB and
$R_{b-{\mathrm{ High}}}$
of up to 70 Mb/s, the reception success rates are >96 and 90% at
$R_{b-{\mathrm{ Low}}}$
of 2.5 and 5 kb/s, respectively.