Tuning technique for active FSS arrays

A novel biasing technique is described for active frequency selective slot arrays. The bandpass response can be switched between transmitting and reflecting modes, or tuned over a predetermined frequency range using two different biasing circuit configurations based on the same technology. The biasing layer is separated from the slot layer by a very thin, flexible, substrate while pin and varactor diodes are employed for switching and tuning, respectively. One application is the time-dependent modification of the EM architecture of buildings, permitting access to frequency bands as desired.