  A system that employs wavelength division multiplexing (WDM) in conjunction
with subcarrier multiplexing (SCM) tones is proposed to realize high data rate
multi-user indoor visible light communication (VLC). The SCM tones, which are
unmodulated signals, are used to identify each light unit, to find the optimum
light unit for each user and to calculate the level of the co-channel
interference (CCI). WDM is utilized to attain a high data rate for each user.
In this paper, multicolour (four colours) laser diodes (LDs) are utilized as
sources of lighting and data communication. One of the WDM colours is used to
convey the SCM tones at the beginning of the connection to set up the
connection among receivers and light units (to find the optimum light unit for
each user). To evaluate the performance of our VLC system, we propose two types
of receivers: an array of non-imaging receivers (NI-R) and an array of
non-imaging angle diversity receivers (NI-ADR). In this paper, we consider the
effects of diffuse reflections, CCI and mobility on the system performance.
