Design And Analysis Of Miniaturized And High-Selectivity Frequency Selective Surfaces

Frequency selective surfaces(FSSs)composed of periodic metal patch or slot elements are artificial electromagnetic surfaces designed to reflect,transmit or absorb electromagnetic fields.Hence,the FSSs are regarded as spatial filters or absorbers.The FSSs composed of patch elements and slot elements are always worked as band-stop and band-pass filters,respectively.The ideal FSSs should have low insertion loss in pass-band and sharp roll off outside of pass-band.Moreover,many applications have the restrict of FSS size.Therefore,this thesis focuses on the study of high selective(sharp roll-off)and miniaturized FSSs.In this thesis,novel compact FSSs with high selectivity and a FSS with miniaturized element have been designed and verificated.The thesis can be divided into the following parts:In the first part,by analyzing the complementary compact microstrip resonant cell(CCMRC),a novel FSS made of a single piece of PCB with double printed metal is presented.The FSS containing two transmission zeros(TZs)near the skirts of pass-band improves the steep roll-offs of the transition between the pass-band and the stop-band.The simulation and measurement results agree well,and the results demonstrate the excellent performance of the FSS.In the second part,by investigating the impact of aperture coupling,a modified FSS based on CCMRC with aperture coupling interlayer is obtained.It can further suppress the transmission property within the stop-band,and adjust the position of the TZs and bandwidth.In addition,the designed FSS presents good angular and polarization stabilities.In the third part,a knitting FSS by combining Jerusalem cross and metal vias has been presented.A conclusion has been drawn that the proposed FSS possess better miniaturization performance.And the influence of the various parameters on the characteristics of the FSS is analyzed.The equivalent circuit model is proposed for the analysis of its working principle.