The Parameter Optimization Of Optical Fiber Sensor With Zno Coating Based On Hybrid Particle Swarm Optimization

The acousto-optic devices have being focused by researchers in optical fiber communications. This thesis studies the ZnO coated optical fiber sensor which has many advantages such as simple structure, low driving energy, large operating frequency range and so on. How to improve the device's power coupling efficiency is a difficult work in making such acousto-optic devices, and the key point is to solve the problem of the device's parameter matching.The influence of ZnO coated optical fiber sensor's parameters on the transmission system was investigated, and the parameters were optimized with genetic algorithm, particle swarm optimization and hybrid particle swarm optimization. The following results have been achieved:Firstly, the relationships among eight parameters such as the reflection coefficient and frequency, the resonator length and piezoelectric layer thickness et al. were analyzed; the impact of device parameters on coupling efficiency was studied; the effect of device parameters on coupling efficiency was compared before and after optimization with simulation experiments.Secondly, the phase shift of an optical fiber sensor with ZnO coating as piezoelectric film was studied intensively; the acousto-optic effect of the device resulting from the application of an electrical signal to the piezoelectric film was analyzed in theory; the phase shift of light traveling through this part of fiber was obtained mathematically and the maximum phase shift simulation results after optimization and experimental results before optimization are compared and analyzed.Thirdly, the objective optimization model for power coupling efficiency was established; the optimization of the model was implemented with genetic algorithm, particle swarm algorithm and hybrid particle swarm algorithm; the optimized results were compared and a set of optics parameters data was obtained from the simulation results, which could provide the theoretical references for the fabrication of the practical fiber sensor with piezoelectric ZnO coating.