BER Analysis of Full Duplex Relay assisted BPSK-SIM based VLC System for Indoor Applications

This paper contemplates a relay-assisted visible light communication (VLC) system, where the light source (Table lamp) acts as a relay node and cooperates with the main light source. Following the IEEE 802.15.7r1 VLC reference channel model, we assume that there are two different light sources present in an office room. The first one is the source terminal present on the ceiling and another one is the desk lamp that serves as the relay station which works in full-duplex method. Because of the loop interference channel, we model VLC relay terminal using ray tracing simulations. We have analyzed bit error rate (BER) performance of the relay-assisted VLC system using binary phase shift keying-subcarrier intensity modulation (BPSK-SIM) technique. The proposed method outperforms existing phase shift keying (PSK) and square M-quadrature amplitude modulation (M-QAM) techniques. The proposed VLC system using BPSK-SIM technique achieves a BER performance of for an SNR of 20 dB. The results of proposed full duplex and half duplex relayed VLC system are evaluated using equal power allocation (EPA) and optimum power allocations (OPA) techniques over three different modulation schemes which are 2-PSK, square M-QAM, BPSK-SIM.