  This paper presents a comprehensive performance analysis of an integrated
indoor power line communication (PLC)/visible light communication (VLC) system
with the presence of a decode-and-forward (DF) relay. The existing indoor power
line networks are used as the backbone for VLCs. The performance of the
proposed system is evaluated in terms of the average capacity and the outage
probability. A new unified mathematical method is developed for the PLC/VLC
system and analytical expressions for the aforementioned performance metrics
are derived. Monte Carlo simulations are provided throughout the paper to
verify the correctness of the analysis. The results reveal that the performance
of the proposed system deteriorates with increasing the end-to-end distance and
improves with increasing the relay transmit power. It is also shown that the
outage probability of the system under consideration is negatively affected by
the vertical distance to user plane.
