Abstract:In this paper, a novel small dual band-notch ultra-wideband planar monopole antenna with switchable functions is presented. Impedance bandwidth of the proposed antenna is approximately 136% with VSWR<2 in the frequency range of 2.2 GHz-11.6 GHz. By inserting a U-shaped slot and SES structures on the patch of antenna, the dual band-notch characteristics are obtainable. The technique of on/off switching of notched bands is based on mounting three pairs of PIN diodes at a certain locations on antenna structure.