An Ultrathin Frequency Selective Surface

This paper proposes an ultrathin high-frequency selective frequency selective surface (FSS), which is composed of three metal layers and two dielectric substrates. The receiving patch and transmitting patches are integrated separately on the top and bottom GND layers, respectively. A stripline central guide structure is etched on the middle GND layer. To improve frequency selectivity, a quarter-wavelength stripline resonator is added. High frequency selectivity is also maintained when electromagnetic waves with oblique incidence angles within 40° are incident on the proposed third-order FSS. The frequency selectivity of the proposed third-order FSS at the left and right edges of the passband is 371 dB/GHz and 386 dB/GHz, respectively. It is indicated that the proposed third-order FSS has high frequency selectivity and wide application in the field of electromagnetic compatibility