Fading-free polarization-sensitive optical fiber sensing.

Area of Science:

• Optoelectronics and Photonics
• Fiber Optic Sensing Technology
• Optical Metrology

Background:

• Conventional polarization-sensitive optical fiber sensors (POFS) suffer from polarization-induced signal fading.
• This fading phenomenon compromises alarm reliability and location accuracy in sensing systems.
• Special locations with minimal polarization change exacerbate signal fading issues.

Purpose of the Study:

• To propose and validate a novel forward transmission POFS scheme to eliminate signal fading.
• To maintain high sensitivity across the entire length of the sensing fiber.
• To enhance the performance of POFS for applications like perimeter security.

Main Methods:

• A forward transmission polarization-sensitive optical fiber sensing scheme was developed.
• Polarization-maintaining fiber was utilized with slow axes spliced at a 45° angle at input and detection ends.
• Theoretical analysis and experimental validation were conducted to assess system performance.

Main Results:

• The proposed system effectively eliminates the signal fading phenomenon.
• The sensing system operates at its maximum sensitivity state.
• Experimental results confirm the theoretical predictions of the enhanced performance.

Conclusions:

• The novel POFS scheme successfully overcomes the limitations of conventional systems by eliminating signal fading.
• The system demonstrates consistent high sensitivity, improving detection reliability.
• This technology holds significant potential for advanced perimeter security and precise physical parameter measurement.