Virtual interfere type optical fibre sensor

Abstract

The invention discloses a virtual interference type optical fiber sensor. The single chip microcomputer is connected with the sinusoidal carrier generation module and the general function signal generation module; the single chip microcomputer is connected with the virtual physical quantity generation module to be measured and the general function signal generation module. The invention simulates various types of interference optical fiber sensors through simple circuit design, and provides a high-precision, high-stability virtual interference optical fiber sensor to output electrical signals, which is convenient for testing and improving various demodulation systems. It can precisely change the virtual physical quantity to be measured, so as to reach each special phase point, and detect whether demodulation errors will occur in the demodulation system at these special phase points. These special phase points are difficult to achieve accurately when using real interferometric fiber optic sensors. Compared with computer simulation technology, the present invention has the characteristics of not introducing high-frequency digital quantization noise, simple structure and the like. Its lower cost and shorter production cycle make it very effective in engineering applications.

Description

technical field [0001] The invention relates to sensors, in particular to a virtual interference type optical fiber sensor. Background technique [0002] The interferometric fiber optic sensor is a sensor that uses the interference of light to achieve a certain physical quantity measurement function. Interferometric fiber optic sensors usually include Michelson interferometric fiber optic sensors, Mach-Zehnder interferometric fiber optic sensors, Fabry-Perot interferometric fiber optic sensors, Sagnac interferometric fiber optic sensors, etc. , Acceleration, micro-vibration, angular velocity, temperature measurement of various physical quantities has been widely used. A typical structure of Sagnac interferometric fiber optic sensor is as follows: figure 1 As shown, it mainly includes a laser, a first coupler, a polarizer, a second coupler, a phase modulator, a fiber ring, a photodetector, and a polarization-maintaining fiber. [0003] Compared with traditional interferome...

AI Technical Summary

Problems solved by technology

However, in the design and testing process of the demodulation system, it will be difficult to directly use the interferometric optical fiber sensor as the output signal source.

First, as figure 1 As shown, the construction of the optical path is cumbersome, and the cost of the vibration-isolation water platform for high-precision measurement is relatively high

Secondly, taking the dual-beam interference fiber optic sensor as an example, since the output and phase are in a periodic relationship, it is extremely important to determine which quadrant the detected phase is in. In actual operation, special phase points often confuse each other.

And in order to detect whether the demodulation algorithm will make mistakes at these points, we need an interferometric fiber optic sensor that can adjust the output very precisely so that the phase value of the output signal reaches these special phase points, which is very difficult during operation

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