A Combined Visible Light and Ultraviolet Communication Approach for Industrial Internet of Things

This paper proposes a dual-spectrum communication strategy for Industrial Internet of Things (IIoT) scenarios that integrates visible light communication (VLC) and ultraviolet communication (UVC). In the proposed approach, VLC leverages existing lighting infrastructure to deliver low-cost, short-range access, while UVC provides reliable backup in VLC dead zones. Given stringent delay requirements in IIoT, finite-blocklength coding is introduced to minimize end-to-end latency. Based on short-packet information theory, the system's achievable rate is analyzed, and the optimal rates under different channel conditions are determined via simulation. An adaptive large-dynamic-range transmission scheme that combines UVC and VLC is designed. The spatial distribution of the rate field is characterized for the hybrid transmission strategy. We conduct bit-error-rate tests in an industrial workshop to validate the performance of the proposed approach, particularly its adequate coverage of UVC in VLC dead zones. It has been demonstrated that UVC can achieve a rate of 0.30 bits/symbol within VLC dead zones.