A high speed quasi-distributed demodulation method based on the microwave photonics and the chromatic dispersion effect is designed and implemented for weak fiber Bragg gratings (FBGs). A novel approach to fibre Bragg grating spectra processing is proposed. By changing the step size of each calculation. This paper introduces a computationally efficient Logarithmic Gaussian Levenberg-Marquardt (LGLM) algorithm for FBG demodulation, which significantly enhances system stability and improves range deviation by more than 11. © 2025 The Author. Our technique exploits the reflection characteristics of fiber Bragg gratings written in polarization-maintaining fibers to create a frequency discriminator, which is able to convert PM/FM signals into intensity-modulated (IM) signals. A simple theoretical analysis is presented to highlight the.
[pdf] Special types are covered in depth, including apodized gratings for suppressing spectral sidelobes, chirped gratings for dispersion compensation and pulse stretching, tilted gratings to create notch filters,.
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