Dual band switchable substrateless frequency selective surfaces

A new means for accurate characterization of substrateless frequency selective surfaces (FSS) was demonstrated with numerical approaches. The RF Schottky diodes model loaded active doubly periodic flat strip FSS acts as a dynamic screen, in which its surface reflectivity and transmittivity can be switched alternately and tuned through d.c. bias voltage control. The characteristic response of a layer of substrateless FSS is found between 3 to 5 GHz. It is shown that by means of d.c. bias control we can utilize the screen in, (a) transmission mode as a dual band electromagnetic shutter, or, (b) reflection mode, as an amplitude shift keying (ASK) spatial modulator or dual band reflection canceller.