Analysis of Communication Link’s Performance of Visible Light Intelligent Transportation System in Sandy Environment

Abstract

In this paper, the performance of the communication link of visible light Intelligent Transportation System (ITS) in sandy environment is studied. $\beta$ is angle between the traffic light axis and the communication link (from traffic lights to vehicles),the relationship between received power at vehicle end and $\beta$ was first analyzed. Then the variation of the background light noise during a day was analyzed. Finally the relationship between Signal-to-Noise Ratio (SNR)/Bit Error Rate (BER) and the visibility in sandy environment during a day was analyzed. The results show that the received power of vehicle decreases with the increase of $\beta$.During a day, background light noise increases and then decreases from 7:00 to 18:30, and reaches the maximum value of about 16 dBm at about 13:00. The change trend of BER is the same, and the change trend of SNR is the opposite. When the visibility is 4km, the maximum difference of SNR between 7:00 and 13:00 is about 20dB, and the maximum difference of BER is about 5.36E-7. At 7:00, the maximum difference of SNR is about 59dB between the visibility of 4km and the visibility of 100km, and the maximum difference of BER is about 1.24E-7.Finally, based on the optical transmission characteristics, a scheme for the visible light intelligent transportation system to adjust the transmitted power according to the real-time visibility is given.