Optimization Analysis And Study Of Effect Of The FSS On Absorbing Properties Of Composite Structure Absorbers

This research focuses on study of a suitable method which analyzes and optimizes composite structure absorbers with multilayer frequency selective surface(FSS) embedded in. In this paper, the computation of multilayer composite structure absorbers was analyzed using fast solution method of generalized scattering matrix cascaded based on the study of propagation mechanisms of electromagnetic waves. According to the influence of various parameters on composite structure absorbers with multilayed FSS embedded in, using optimization algorithm design composite structure absorbers with low reflection coefficient, wide absorption band and thin layer thickness was investigated.Firstly, composite structure absorbers with multilayer FSS embedded in were subdivided into multiple subsysmtems independently. Propagation mechanisms of electromagnetic waves in subsystems and dielectrics and boundary conditions of the interfaces of subsystems were analyzed respectively. Based on finite element method and generalized scattering matrix cascading technique. The fast solution method of generalized scattering matrix cascaded which was suitable for calculating reflection coefficient of composite structure absorbers with multilayer FSS embedded inin were obtained. Further using this method to calculate the specific composite structure absorbers with multilayer FSS embedded in, compared the 3-D numerical method of calculating results, verified the correctness of the fast solution method of generalized scattering matrix cascaded.On the basis of the above research, the influence of various parameters on absorbing properties of composite structure with Y, cross and jerusalem FSS embedded in respectively were studied. Firstly, a cross FSS was designed and embedded in two layers of absorbing materials.Then the embedded FSS significantly increases absorbing bandwidth wider and absorption property stronger.These were verified through analysing frequency reponse characteristics of this composite structure absorber.Further the influence of parameters such as medium thickness, FSS sizes, incident angle under different polarization modes on the absorption property of the composite structure were studied.In order to get the good absorbing properties in composite structure, according to the research on influence parameters of composite structure, setting up reasonable boundary values of various parameters, by using the differential evolution algorithm for all parameters of the composite structure absorbers with multilayer FSS embedded in optimization design, in working frequency range, obtained the good performance of the composite absorbing structure.