Reconfigurable frequency selective surface for use in secure electromagnetic buildings

Practical measurements of a reconfigurable frequency selective surface (FSS) designed to stop the transmission of the GSM network protocol are shown. The method uses the time-varying transmission phase of the FSS to impair a GSM signal transmitted into a building or room, such that the receiver cannot detect the incoming signal. Measurements of the FSS response are shown for varying reconfigurable states and the FSS has been tested against a GSM signal to observe the level of impairment offered by the FSS. It is shown that the FSS can provide up to 35% bit error rate.