Frequency Selective Structure with Transmission and Scattering Deflection Based on Spoof Surface Plasmon Polariton Modes

A novel method of designing the frequency-selective structure (FSS) with transmission and scattering deflection based on spoof surface plasmon polariton (SSPP) modes is proposed and demonstrated in this paper. High-efficiency transmission based on SSPP modes coupling can be achieved below the cut-off frequency using the metallic fishbone structure (MFS). As the composed blade length is varied, the dispersion of the SSPP mediated on the MFS keeps almost unchanged in the low-frequency band, while has an obvious change in the high-frequency band. Therefore, the FSS with transmission and scattering deflection can be achieved by a reflection-type coding metamaterial using the MFS. To verify this idea, the FSS was simulated, fabricated, and measured. Under linearly polarized wave normal incidence, the transmissivity of the FSS exceeds −0.8 dB below the frequency f = 9.5 GHz. In the stopband, the radar cross section (RCS) reduction is higher than 10 dB from 14.4 to 18.0 GHz, which results from the anomalous reflection due to the 1 bit 0101/1010 coding sequence. The FSS with transmission and scattering deflection based on SSPP modes can be applied to the electromagnetic windows of vessels.