Indoor visible light communications: performance evaluation and optimization

Abstract

For indoor visible light communication (VLC), much work has been done when the noise is independent of the input signal. However, less effort is made when the VLC system suffers from the input-dependent noise. Considering the input-dependent noise, this paper focuses on the performance analysis and optimization for indoor VLC system. The Lambertian emission-based channel model and on-off keying modulation are employed. According to the system model, the bit error rate (BER) with a closed-form expression is derived. To enhance the system performance, an optimization problem that minimizes the BER by tilting the receiver plane is formulated. By solving the problem, the optimal tilting angle of the receiver is obtained. Simulation results verify the derived expression of BER. It is also shown that the BER is strongly affected by the input-dependent noise. Moreover, the optimal tilting angles for the receiver at any position are obtained, which can provide some insights for practical system design.