Demonstration of Inter-cell Interference mitigation in multi-cell VLC systems using optimized angle diversity receiver

In this paper, we numerically and experimentally demonstrate an inter-cell interference (ICI) mitigation scheme for multi-cell visible light communication (MC-VLC) systems using optimized angle diversity receivers (ADRs). An ADR usually consists of a non-tilted top detector and several tilted side detectors. We optimize the performance of the ADR by choosing an optimal tilting angle of each side detector. In comparison to the conventional frequency allocation-based ICI mitigation schemes, the optimized ADR-based ICI mitigation scheme enjoys three main advantages: 1) high cell capacity; 2) improved signal-to-interference-and-noise ratio (SINR); 3) reduced SINR fluctuation. The feasibility of using optimized ADRs for ICI mitigation in indoor MC-VLC systems is verified by both numerical analysis and experiments. Experimental results show that a two-cell VLC system using an optimized ADR can achieve an SINR improvement of 18.6 dB and a 1-dB SINR fluctuation, compared with the same VLC system using a single-element receiver without angle diversity.