Abstract: A fiber Bragg grating（FBG）demodulation method based on nonlinear edge filter is used. Its basic principle is to use the ratio of two light signals to compute physical quantities. But under the condition of the same physical quantities, as energy of light source is changed, the ratio of two light signals has a small difference. Therefore, the instability problem of the system can be found and the ratio value correction method is used to solve the problem. The instability problem should be widespread in all light intensities demodulation methods such as edge filter demodulation method and matched filter demodulation method. In order to simplify the relationship between physical quantities and the ratio, Omit the wavelength that is the middle physical quantity, we use the method of virtual wavelength. The relationship between the actual wavelength and virtual wavelength is established. Compared with demodulation method of linear edge filter, our method can not only solve the instability problem and can improve the wavelength accuracy, but also can simplify the process.
Keywords: fiber Bragg grating demodulation, virtual wavelength method
Title: A FBG Demodulation System Based On Nonlinear Edge Filter and the Virtual Wavelength Method
Author: Xichang Wang
International Journal of Mechanical and Industrial Technology
ISSN 2348-7593 (Online)
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