Quasi-Omnidirectional Vehicular VLC: Design, Implementation, and Experimental Validation

Visible Light Communication (VLC) is emerging as a compelling solution for future vehicular networks due to its high bandwidth and immunity to radio frequency (RF) interference. However, its relatively directional nature poses significant challenges in dynamic driving environments. This paper presents the first comprehensive experimental evaluation of a quasi-omnidirectional vehicular VLC system integrating dual headlight transmission with six photodetector (PD) receiver architecture. The system is implemented on a software-defined radio (SDR) platform and evaluated across a range of real-world driving scenarios including curved roads, intersections (T-and Y-junctions), and multilane settings. Through extensive outdoor measurements under static and mobile conditions, we demonstrate that our system achieves 100% packet delivery ratio (PDR) up to 15 meters in all scenarios and up to 29 meters under ideal alignment. We further compare select best combining (SBC) and equal gain combining (EGC) schemes, identifying SBC as the superior approach due to its noise robustness. Our findings show that strategically placed side and rear PDs play a critical role in maintaining connectivity during vehicular maneuvers, such as lane changes and turns. This study validates the feasibility and effectiveness of multi-PD vehicular VLC systems and provides key design insights for their integration into Intelligent Transportation Systems.