  This paper presents an indoor visible light communication (VLC) system in
conjunction with an imaging receiver with parallel data transmission (spatial
multiplexing) to decrease the effects of inter-symbol interference (ISI). To
distinguish between light units (transmitters) and to match the light units
used to convey the data with the pixels of the imaging receiver, we propose the
use of subcarrier multiplexing (SCM) tones. Each light unit transmission is
multiplexed with a unique tone. At the receiver, a SCM tone decision system is
utilized to measure the power level of each SCM tone and consequently associate
each pixel with a light unit. In addition, the level of co-channel interference
(CCI) between light units is estimated using the SCM tones. Our proposed system
is examined in two indoor environments taking into account reflective
components (first and second order reflections). The results show that this
system has the potential to achieve an aggregate data rate of 8 Gb/s with a bit
error rate (BER) of 10-6 for each light unit, using simple on-off-keying (OOK).
