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Testing vehicle-to-vehicle visible light communications in real-world driving scenarios

Vehicle-to-vehicle (V2V) communications utilizing visible light communications (VLC) have become an attractive solution to provide a reliable and highly scalable communication link. In this paper, we perform the first-ever real-world driving test of a V2V VLC prototype, with two cars driving on a highway in a car-following setting for a total of 108 kilometers. Utilizing a number of software and hardware techniques and OFDM waveforms, our system can reliably achieve a working range of 45 meters. Experimental results show that multipath propagation has little effects to the error performance, while the distance and the angle are the two main factors determining the received power and thus the error performance. They also demonstrate extremely stable links, which generates no reception error for up to 50 seconds in many occasions. Finally, we also investigate a number of specific cases which cause reception errors, such as another vehicle overtaking the receiver and interference from nearby LED signage. We hope the lessons learned from this study can provide guidelines to future system designs.