Research And Design Of Miniaturized Stealth And Protection Device Based On Metasurface

With the economic digitization and military informatization,the security of electronic communication system has become a vital section in the economy and national defense construction.Strong electromagnetic pulse can instantly destroy the unshielded electronic communication system.The electromagnetic stealth and protection of communication equipment are urgently needed.In this paper,the principles and implementations of a miniaturized transmission/absorption integrated frequency selection surface(FSS)with ultra-wide absorption band and a miniaturized dual-band wide-band absorptive energy selection surface(ESS)are researched,as follows:1)A miniaturized transmission/absorption integrated frequency selection surface with ultra-wide absorption band is proposed.It consists of band-stop FSS and band-pass FSS.By loading capacitors between the gaps of the band-pass FSS,the miniaturization is realized.As a result,the grating lobes in the absorbing band are successfully suppressed,and the stealth performance of integrated FSS is improved.By cascading the resistive band-stop FSS and band-pass FSS,the absorption bandwidth of integrated FSS is widened.Further,corresponding equivalent circuit model is proposed,and the principle of ultra-wideband absorption is analyzed.The results show that the insertion loss of integrated FSS at 2.2 GHz is only 0.6 d B,and the absorption bandwidth greater than 90%is 12.6 GHz(6.8-19.4 GHz).2)A miniaturized dual-band wideband absorptive ESS is proposed.It consists of an absorptive metasurface loaded with resistances and a switchable metasurface loaded with PIN diodes.When low-power signals are incident,the ESS operates in transmission mode,in-band signals are allowed to be transmitted,while out-of-band signals are effectively absorbed.When high power microwaves(HPM)are incident,the ESS changes to protection mode.The HPM in the passband are reflected and those out-of-band are absorbed.Besides,by loading lumped capacitances between the metal patchs,multiple LC parallel resonators are introduced and dual-band transmission is realized.At the same time,vias are added to the switchable metasurface,the current path between its dielectric layers is increased,and the miniaturization can be realized.The results show that in transmission mode,the ESS has two transmission windows at 3.10 and 4.06 GHz with insertion losses of 0.83 d B and 0.72 d B respectively,and an absorption band range of 6.84-18 GHz.While in protection mode,the shielding effectiveness of the ESS are 35 d B and 36 d B respectively,and the absorption bandwidth is 11.32 GHz(6.68-18 GHz).