Research On Analysis Of Fiber Bragg Grating Reflection Spectrum With Particle Swarm Optimization Algorithm

Because fiber Bragg grating(FBG) has the advantages of resistance to electromagnetic interference, excellent insulation, corrosion resistance, easy for fiber connection, realizing wavelength absolute coding, easy for multiplexing, etc, FBG sensor as one of the faster-developing technology has been widely used in the field of aerospace,civil engineering, petrochemicals, medical treatment, electric power, and so on. In the analysis of FBG reflection spectrum, there are some system mistake and some uncertain parameters during experiment,so it is difficult to extract the characteristic information in a FBG reflection spectrum accurately. In this paper, a new methods which is using the Particle Swarm Optimization (PSO)algorithm to identify characteristics of reflection spectrum and characterize the amount of FBG sensing is proposed, which specifically includes:Embark on the transmission of FBG, the establishment of FBG’s reflected spectrum model under axial force, transverse force and twist angle was introduced based on Mode coupling theory and transfer matrix method.And a detailed theoretical analysis was carried out, characteristics of reflection spectrum which reflects external signal was extracted. The relationship between the feature information and sensing information was given. The sensing experiment system of FBG has been designed and the experiments were carried on respectively to FBG under the axial force, the transverse force and the twisted action. And the theory had been confirmed accuracy.Meanwhile,faced on the alteration of FBG reflection spectrum under the force and some uncertain parameters, Improved particle swarm optimization model was established based on standard model of particle swarm optimization. And the testing software of corresponding algorithm was compiled.The reliability and stability of designed particle swarm optimization was tested Through the optimization of test functions. Also the parameters which impact the algorithm were analyzed.And the optimized feasibility of the application was tested by a large number of FBG simulation model. Finally, object to FBG under axial uniformforce and the transverse uniformforce, the corresponding objective functions for optimization testing were designed.The results of experiments show that PSO algorithm has feature of high accuracy, speed, good stability and so on,and has the capability to analyze other information which is not easy to measure. Therefore, particle swarm optimization algorithm has a certain practicality and advanced in analysis of FBG reflection spectrum.