Enhanced three-lane vehicle visible light communication system

This paper aims to improve the traffic system through an imaging receiver. Different modulation schemes for visible light communication (VLC) are investigated, including On–Off Keying (OOK), L-Pulse Position Modulation (L-PPM), and Inverse L-Pulse Position Modulation (I-L-PPM) schemes. Considering a road with three lanes, the received information changes according to many factors such as the communication distance and the number of pixels for the imaging receiver. A simple traffic model has been proposed and analyzed for optimizing several remarkable characteristics, including signal to noise ratio (SNR), required average power, bit error rate (BER), and modulation scheme. The simulation results show that, an imaging receiver with 64 × 64 pixels is a good choice for a communication distance in the range 10–50 m between vehicle and traffic light. Also, in the three lanes, the received information increases with the number of pixels. The replacement of a photodiode with an imaging receiver enhances the SNR and reduces both required transmitter power and BER. It is found that 10 dB less power is required in 16-PPM scheme requires than that required by the 16-I-PPM, but in the expense of bandwidth used.