Differential Receiver as a Denoising Scheme to Improve the Performance of V2V-VLC Systems

摘要

Visible light communications (VLC) system is an emergent technology to enhance the security of road transportation by enabling wireless communications between vehicles and with the traffic infrastructures. Ambient light noise, due to the sunlight irradiance and other surrounding light sources, is a major concern that degrades the performance of the VLC system in outdoor application in terms of signal to noise ratio (SNR) and bit error rate (BER). In this paper, the effect of sunlight irradiance and other external sources are investigated for vehicle to vehicle (V2V) communication system in visible light environment with regard to SNR, BER and data rate. A differential receiver scheme is proposed as a solution to mitigate the effect of the sunlight noise. We investigate the system performance for three scenarios: without optical filter, with optical filter, and with proposed differential receiver. Simulation results show that differential receiver can predict about 50% of sunlight irradiance and can improve the BER from 5 × 10~(-4) up to 5 × 10~(-5) within the test area. Moreover, the results depict V2V-VLC system can still work under sunlight irradiance where the worst achievable BER during June is {approx.-} 5 × 10~(-4).