Active Wideband Polarization Insensitive Absorber for Ku and K-Band

This paper presents a simplified active frequency selective surface (AFSS) design with a wide tuning frequency range. The structure uses four variable resistance p-i-n diodes (NXP BAP 70–03) to achieve this characteristic. Secondly, the biasing complexity of the AFSS is simplified. The AFSS operates with -10 dB reflectivity in the 17.5-21.5 GHz and in both transverse electric (TE) and transverse magnetic (TM) modes. The unit-cell design strategy to achieve this response is discussed.