Novel Frequency Selective Surfaces with compact structure and ultra-wideband response

A novel bandstop Frequency Selective Surface (FSS) is presented, in which a unit cell consists of two metallic of spiral strips of different lengths and a dielectric substrate in the middle. Both simulation and measurement are presented to show that the FSS can realize size reduction and ultra-wideband response. By changing the lengths of some outer strips the miniaturization amount and bandwidth can be adjusted. Moreover, all these responses are stable with respect to different incident angles, which make the proposed structure more valuable for practical application.