Fiber ring-down loop time division multiplexing sensing system

Abstract

The invention provides a fiber ring-down loop time division multiplexing sensing system. The system comprises a plurality of fiber ring-down loops, a light source, a light source driving module, a pulse generator, a signal acquisition and processing device, a photoelectric converter and a temperature control module, wherein, each fiber ring-down loop comprises an input coupler, an output coupler and a sensing probe, the light source driving module receives a pulse signal of the pulse generator and controls the light source to output light pulse, pulsed light enters into each ring-down loop and changes into a ring-down pulse signal respectively, ring-down pulse signals return to the photoelectric converter according to a time sequence, one side of the signal acquisition and processing device is connected with the pulse generator to obtain a synchronization signal, the other side of the signal acquisition and processing device is connected with the photoelectric converter and carries out processing and storage on an electric signal outputted by the photoelectric converter, and the temperature control module controls an operating temperature of the light source and feeds back the operating temperature to the signal acquisition and processing device simultaneously. According to the system, multi-point and multi-parameter real-time measurement in a severe environment can be realized.

Description

technical field [0001] The invention relates to a time-division multiplexing sensing system of an optical fiber ringdown ring. Background technique [0002] Optical fiber ring-down spectroscopy is a fiber optic sensing technology derived on the basis of cavity ring-down spectroscopy (G.Berden, R.Peeters and G.Meijer, Cavity ring-down spectroscopy: Experimental schemes and applications, Int. Reviews in PHYSICALCHEMISTRY, 2000, Vol.19, No.4, 565-607). Cavity ring-down spectroscopy is a sensitive absorption spectroscopy technique because it measures the proportion, rather than the magnitude, of an optical pulse absorbed in an optical cavity. The gas sample is placed in a high-precision optical cavity consisting of two highly reflective mirrors. When a narrow pulse of light is coupled into a cavity, the light is reflected back and forth in the cavity, with a small portion of each reflection leaking out of the cavity. Instead of measuring the total intensity of light in the ca...

AI Technical Summary

Problems solved by technology

[0003] The biggest problem in the practical application of cavity ring-down spectroscopy comes from the extremely high technical requirements for the optical cavity. It is necessary to maintain its extremely low inherent loss and match the resonance of the cavity, and the requirements for coating and polishing precision in the cavity manufacturing process are high and Expensive

Secondly, the optical cavity is very sensitive to the application environment, and cannot be applied in a harsh environment, nor can it develop a distributed remote detection system

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