Study On Design And Tuning Methods Of Sampled Fiber Gratings With Special Structure

Fiber Bragg Grating (FBG) which is as an important optical passive device has extensive and important applications in optical fiber communication,optical fiber sensing and optical information processing. With DWDM technology development, sample fiber Bragg grating,because of their tunable multi-wavelength reflection peak,plays an increasingly important role in multi-wavelength tunable narrow-band laser, multi-wavelength tunable narrow-band filter, dynamic dispersion compensation.Sample fiber grating which is in accordance with the different sample functions is divided into amplitude sample fiber grating and phase sample fiber grating, amplitude sample fiber grating theory and experiment now are more mature, a variety of device based on fiber grating amplitude sample has been widely used in optical fiber communications, optical fiber sensing and other fields. Phase fiber Bragg grating requires a very high experimental precision because of its complex phase-shift phase change, phase sample fiber grating therefore relatively develop slowly, but also because of the diversity of phase change gratings, phase sampled fiber grating shows a number of new spectrum characteristics, and so has potential applications in multi-channel filters, dispersion slope compensation.This article focuses on a special structure for the sampled fiber grating, such as the phase sample and amplitude grating with phase sampling theoretical analysis and numerical simulation, and tuning of sampled grating method, the main results obtained are as follows:(1)The amplitude of the sampled fiber grating types are calculated and simulated, in order to improve the matrix sample which is showing as the Sine function envelope distribution and inhibit sidelobe, respectively, use Sine sample function and Gauss Apodization to optimize the reflection spectrum; then do an analysis of a phase amplitude sampled combined fiber grating, without changing the conditions of the sampling period, two phase shift of a certain size to achieve is added to the amplitude of each sample in order to decrease the channel spacing, increase the number of channel.(2)Do an analysis of the theory of phase-sampled fiber grating, make optimization of the phase distribution of phase fiber grating based on simulated annealing algorithm, in conditions of shorter length and lower refractive index grating modulation strength, reflection spectrum obtains 32 reflections peak channel and its spacing is 0.8nm. (3)Fiber grating wavelength tuning method of exploration and technology development is still a hot topic in the field of optical communication and optical sensing, based on a detailed comparative analysis of advantages and disadvantages of the common tuning technique,this paper study on an improved temperature tuning method, which can adjust the length of packaging material to achieve the sample fiber grating temperature sensitivity adjustment, and without the adhesive of the grating part, avoid the reflection spectrum chirp due to Curing adhesive, obtain a multi-wavelength, quasi-free chirp,high linearity of the temperature tuning effect.