无偏置网络场控有源频率选择表面设计

Design of an active frequency selective surface without biasing grids

普通有源频率选择表面(AFSS)均存在直流偏置网络,用于在有源元件两端加直流偏置。提出一种新的有源频率选择表面设计方法,利用电磁波在频率选择表面加载元件两端产生的感应电压作为偏置信号,对频率选择表面的传输特性进行控制。仿真结果表明:频率选择表面在小场强辐照下,其在3.5GHz存在通带;当电场强度大于70V/m时,电磁波在3.5GHz处的插入损耗逐渐增大;当入射微波场强达到5000V/m时,插入损耗达20dB左右。实验结果与仿真结果基本吻合。

All conventional active frequency selective surfaces （AFSS） are, without exception, designed with a DC biasing circuit to impose DC biasing voltage across active components. An innovative method to design AFSS is proposed in this paper to generate an induced voltage across both ends of the surface load- ing components as the biasing signal to control FSS＇s transmission properties. The simulation result indi- cates that a pass band exists on the AFSS at 3.5 GHz when it is exposed to an electric field at a smaller in- tensity; when the Electric Field Intensity （EFI） is over 70 V/m, the insertion loss of the electromagnetic wave （EMW） increases at 3.5 GHz; in the case that the incident microwave＇s field intensity reaches 5 000 V/m, the insertion loss is over 20 dB. Overall, the experimental result is basically consistent with that from simulation.