Design And Analysis Of Multiple And Broadband Frequency Selective Surface

With the rapid development of wireless communication technology,multi-band and broadband communication technologies are becoming a hot research topic.Frequency Selective Surface(FSS)is an important role in communication system The transmission and reflection of the incident electromagnetic wave can be effectively controlled by the FSS which is a periodic structure.The multi-band and broadband properties of the FSS have been widely studied.Closely focus the multi-band and broadband properties of the FSS,two kinds of the FSS has been designed in this thesis.The major contributions are summarized as follows.(1)First,the background,developed history and the research status of the FSS have been described.Then,a study about FSS is carried out on elementary theory and working principle.Some FSS analysis methods are introduced,it such as moment method,finite element method,equivalent circuit method,etc.Meanwhile,two test methods of FSS are also introduced and comparative analyzed in detail.(2)A novel dual-band FSS is proposed by loading metal of three-dimensional structure technique.The novel thin FSS cell is composed of two metallic layers separated by a dielectric spacer and a cross chunks of metal.The thickness is only 1mm.The influence of the incident angle variation on the bandwidth,central frequency and transmittance of the proposed structure are investigated when TE and TM waves are used as incident waves.Simulation results show that the novel FSS has a better transmission properties with polarization independence and incident angle independence.(3)A miniaturization and broadband novel double-layer FSS is proposed by adding circular holes to the square loop and circular patch.Based on the equivalent circuit model method,the novel FSS structure are analyzed theoretically.The bandwidth,central frequency and transmittance of the structure are investigated when some parameters including the incidence angle and polarization at big incident angle are changed.By optimizing the geometric parameters of the novel FSS,a double-layer FSS with a side of 0.12?,and a thickness of 0.09?,is obtained.Simulated and measured results show that the proposed FSS has a good performance in wideband,polarization insensitive,wide-incident angle,miniaturization and sharply decreased.The proposed FSS can also be applied in K-band and Ka-band.