In recent years, visible light communications (VLC) have been developing rapidly in many applications. Although VLC can be applied in many scenarios, a key barrier for its widely deployment is the line-of-sight (LOS) transmission nature since the direct link can be easily blocked by obstacles. To address the link blockage issue in VLC, we propose an omni-digital reconfigurable intelligent surfaces (Omni-DRIS) enhancement VLC system architecture, named Omni-DRIS system, which makes use of the reflection and refraction natures of Omni-DRIS. By deploying Omni-DRIS in one room, we first propose the joint use of LEDs in two rooms to combat blockages. To study the bit error rate (BER) performance of Omni-DRIS system, we derive mathematical expressions and use Monte Carlo simulations to validate the analytical results. Based on the simulation results, we find that when the system’s links are free from blockages, the Omni-DRIS system achieves an approximate one-orders-of-magnitude improvement in BER performance compared to the OneRIS system and an approximate three-orders-of-magnitude improvement compared to the NoRIS system. When system has random blockages, the Omni-DRIS system achieves an approximate two-orders-of-magnitude improvement in BER performance compared to the OneRIS system. Our findings reveal that the use of Omni-DRIS can significantly improve system BER performance if the room has random blockages. In the future, Omni-DRIS can be better controlled using intelligent algorithms to further optimize the system performances. Our first attempt in applying OmniDRIS to the scenario where one room’s LED is totally blocked is of great importance for the future large-scale deployment of Omni-DRIS assisted VLC system.
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