Designs And Investigations Of Bandpass Frequency Selective Surface Based On Paper-like Honeycomb Structure

Frequency Selective Surface(FSS)is a two-dimensional(2-D)periodic array structure formed by identical metal and medium units arranged and distributed along certain periodicities.It has selective regulation characteristics for incident space electromagnetic waves with different frequencies,polarizations,and phases.It is widely used in electromagnetic compatibility,anti-electromagnetic interference and other aspects.The paper-like honeycomb is a new type of composite material,which has the advantages of light weight,high stiffness and high strength.Therefore,this paper explores and designs a series of bandpass FSS based on paper-like honeycomb structure by the threedimensional(3-D)slotline FSS to provide solutions for the realization of lightweight and high mechanical properties of the new FSS.Two kinds of high performance three dimensional FSS with different functions are proposed,which provides a design idea for the space electromagnetic wave control devices with coupled-slotline FSS in various functions.The research contents are as follows:1.Based on the 3-D slotline FSS,a paper-like honeycomb structure bandpass FSS is proposed.Firstly,the filtering performance of the basic slotline resonator is discussed and analyzed.A wide stopband single polarization trough FSS is designed by means of stepped-impedance resonator(SIR),short-circuit inductor and quarter-wavelength short-circuit resonator.Furthermore,the full-wave analysis of single-polarized slotline FSS placed on the honeycomb wall is carried out to determine the cell structure of the honeycomb FSS by using electromagnetic simulation software HFSS.Finally,the single-polarized FSS was printed on high-strength aramid paper by screen printing technology,and the paper-based honeycomb FSS was processed according to the predetermined simulation model.The results of full-wave simulation and test validate the feasibility of designing and machining the honeycomb FSS.2.Based on the 3-D coupled-slotline FSS,two high-performance bandpass FSS are proposed.Firstly,the odd-even mode impedance of the first-order coupled-slotline resonator is extracted and analyzed,which provides guidance for the design of coupled-slotline FSS.Then the resonant mode of the second-order coupled-slotline is analyzed,and the SIR is used to suppress the stray coupling mode in the second-order coupled-slotline FSS.A bandpass FSS with wide stopband characteristics based on the coupled-slotline is designed.Furthermore,on the basis of the second-order coupledslotline FSS,a T-type stub is loaded at the central axis of the structure.The full-wave simulation results show that the proposed design can suppress a transmission zero at the low frequency of the passband,and achieve the multi-mode resonance of four transmission poles in the in-band and two transmission zeros in the out-of-band.A bandpass FSS with quasi-elliptic filtering response based on coupled-slotline is proposed.Finally,the second FSS design object was fabricated and assembled.The good agreement between the test results and the simulation results verified the correctness of the design scheme.3.Based on the 3-D coupled-slotline FSS,two kinds of paper-like honeycomb bandpass FSS with different processes are designed.Firstly,a metal-aluminum honeycomb process is considered,and a single-polarized FSS design consisting entirely of metal-aluminum is introduced.The design consists of a first-order coupled-slotline resonator.Then it is adapted to the honeycomb wall,and an aluminum honeycomb FSS design with asy mmetric polarization but consistent operating frequency is proposed.The polarization difference and unique oblique incidence of the topology of the honeycomb arrangement are analyzed.Secondly,the paper-based honeycomb process is considered,and a secondorder coupled-slotline FSS design is adapted to the paper-based honeycomb wall,and a paper honeycomb FSS design with excellent single-side filtering response is proposed.In addition,the design also analyzes and inhibits the parallel plate waveguide coupling in the paper-based honeycomb process.The simulation results show that the two honeycomb FSSs exhibit excellent filtering response and oblique incidence stability,and have high application potential.