Dual-band filtering antenna with controllable frequencies and bandwidths

This paper presents a dual-band filtering antenna with sharp frequency selectivity and high out-of-band radiation rejection levels. It consists of two U-shaped patches and a feed network. When the lower band U-shaped patch is excited, the upper band patch does not radiate and vice versa by using a novel feed scheme. Thus, the two operating bands can be independently controlled by tuning the dimensions of each U-shaped patch. To verify the design concept, a dual-band filtering antenna operating at 5.2 and 5.8 GHz is realized and the results are presented.