Fiber bragg grating (FBG) sensing demodulation device and method based on reflective semiconductor optical amplifier (RSOA)

Abstract

The invention discloses a fiber bragg grating (FBG) sensing demodulation device based on a reflective semiconductor optical amplifier (RSOA). The FBG sensing demodulation device comprises a tunable laser, an optical circulator, a photoelectric detector and a processing and control unit, wherein the tunable laser comprises the RSOA, an optical coupler and a tunable FBG unit in sequential connection. The invention also discloses an FBG sensing demodulation method based on the RSOA. The sensing demodulation device and the sensing demodulation method realize the FBG sensing demodulation with the advantages of high speed, low cost and simple structure.

Description

technical field [0001] The invention relates to the technical field of FBG sensing demodulation, in particular to an FBG sensing demodulation device and method. Background technique [0002] Optical sensing, especially optical sensing based on fiber grating technology, is currently used in many fields such as civil engineering, petroleum, electric power, transportation, mining, medicine, etc. field has been widely used. The structure of fiber grating sensing and demodulation system based on tunable laser is as follows: figure 1 As shown, it generally consists of tunable laser, FBG (Fiber Bragg Grating, fiber Bragg grating, referred to as fiber Bragg grating) sensor (FBG1 ~ FBG4), photodetector and optical passive device ( figure 1 In the optical coupler) and other parts. Among them, the physical quantity to be measured encodes the wavelength of the reflected light through the FBG sensor. The narrow-band optical signal sent by the tunable laser is coupled by an optical cou...

AI Technical Summary

Problems solved by technology

Among them, the thermal tuning method is limited by the response speed of the thermal effect, and the tuning speed is relatively slow, so it is difficult to realize high-speed dynamic measurement of the FBG sensor

The fiber F-P cavity length tuning method is to coat the fiber end face with a high-reflection film, use the fiber end face to form an F-P cavity, and tune the F-P cavity length to realize the tuning of the laser output light wavelength. This method has the disadvantages of complex coating on the fiber end face and high cost.

Therefore, the currently used methods have shortcomings such as high cost, complicated manufacturing process, or low tuning speed, and difficulty in supporting high-speed dynamic measurement, which greatly restricts the development and application of FBG sensing technology.

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