Passive-active hybrid FBG-power-over-fiber system for integrated sensing, power delivery, and communication

Despite advancements in optical fiber sensing and power transmission technologies, existing systems face challenges of redundant multi-device deployment and incoordination between power supply and communication under complex working conditions such as strong electromagnetic interference, hazardous areas, or long-distance monitoring. This paper proposes a passive-active hybrid fiber Bragg grating (FBG) fiber-powered system, integrating sensing, power supply, and communication functions through a single-fiber architecture. The system utilizes the reflected spectrum of the FBG for wavelength demodulation, harnesses the transmission spectrum to supply DC power to remote low-power sensors, and establishes a high-speed backhaul channel based on the low-loss transmission characteristics of the FBG at the 1310 nm wavelength. Experimental results demonstrate that the system simultaneously achieves FBG temperature sensing (sensitivity: 9.7 pm/°C), power supply to electronic temperature monitoring nodes, and 1.25 Gbps error-free communication (BER < 10^-12) over a 20-km single-mode fiber. This provides an innovative solution for reliable monitoring in high-risk scenarios such as petrochemical plants and power grids.