A miniaturized transmission/absorption integrated frequency selection surface with ultra‐wide absorption band

In this paper, a miniaturized integrated frequency selective surface (FSS) is proposed. It is composed of two parts: the band-stop FSS and band-pass FSS. Through introducing six capacitors between the hexagonal gap of band-pass FSS, a miniaturized dimension of 0.07λ0 × 0.07λ0 × 0.036λ0 (λ0 is the wavelength of the transmission band in free space) is achieved. As a result, the presented FSS effectively avoids grating lobes and remains stable when the incident angle changes. In addition, by coupling between the band-stop and band-pass FSSs, the ultra-wide-band absorption is realized. The results show that the insertion loss at 2.2 GHz is only 0.6 dB and the bandwidth with the absorptivity larger than 90% is 12.6 GHz (6.8–19.4 GHz). Besides, the integrated FSS has good polarization and angular stability.