Study of active periodical structure's controlling the direction of reflector electromagnetic wave

The conception of active reflection was presented. Using the periodical surface's character of band gap and impedance transition of electromagnetic crystal structure such as photonic band gap(PBG), frequency selection surface (FSS), high impedance surface (HIS) and so on, the varactor diode was put onto the approximate HIS's surface to join each cell of metal on top layer to realize the electronic control for periodical structure. The active periodical structure was established. The propagation characteristic of incident electromagnetic wave was effected and controlling the reflected phase and direction of reflector electromagnetic wave were realized. The simulation test proves that this method and technology can control reflector wave's phase and direction of on working frequency band by using single or double layer active periodical structure effectively.