Microwave assisted reconstruction of optical interferograms for distributed fiber optic sensing

Area of Science:

• Optoelectronics
• Fiber Optic Sensors
• Microwave Photonics

Background:

• Distributed fiber optic sensing offers a powerful method for monitoring physical parameters over long distances.
• Traditional methods can face challenges in sensor resolution and multiplexing capabilities.
• Interferometric techniques are sensitive but often require complex signal processing.

Purpose of the Study:

• To develop and demonstrate a distributed fiber optic sensing technique capable of resolving multiple sensors along a single fiber.
• To utilize microwave modulation for enhanced separation and reconstruction of optical interferograms.
• To validate the technique's accuracy and its application in distributed strain measurement.

Main Methods:

• A microwave-modulated optical signal was transmitted through cascaded fiber optic interferometers.
• Microwave signals were employed to determine the position and reflectivity of individual sensors.
• Optical spectrum sweeping and modulation signal detection allowed for the reconstruction of each sensor's interferogram.
• Extrinsic Fabry-Perot interferometric sensors were used for experimental validation.

Main Results:

• The microwave-assisted reconstruction of interferograms from cascaded sensors showed excellent agreement with individual measurements.
• The technique successfully demonstrated its capability for distributed strain measurement.
• Accurate localization and characterization of multiple fiber optic sensors were achieved.

Conclusions:

• The proposed microwave-assisted distributed fiber optic sensing technique provides an effective solution for multiplexing and precise measurement.
• This method offers a robust approach for real-time monitoring in various applications requiring distributed sensing.
• The successful demonstration with extrinsic Fabry-Perot interferometers highlights the technique's versatility and potential.