AF Cooperative VLC Communication Systems: Cascaded Channel Analysis

摘要

Visible light communications (VLC) technology is a relatively new emerging telecommunication paradigm. It offers the opportunity to design cost-effective communication systems due to the dual use of the light sources, which are exploited as illumination devices and as communication antennas. However, this technology is mostly deployed in short-range communication applications because of the light diffusion range, which is short by nature. One good response to this dilemma is the implementation of relay-assisted cooperative communication systems. Cooperative VLC systems provide three advantages, which are an increase in the transmission range, an improvement of the detection, hence of the bit error rate (BER), and an improved lighting system. In this paper, we analyze the channel response of a single-relay indoor VLC system based on an amplify-and-forward (AF) strategy. The system takes into account the fact that the relay also receives a reflected message. Results show the influence of the room's reflection index, Lambertian index, the number of scattered rays on the overall channel response and confirms the importance of relay-assisted strategies in improving system's reliability.