Compact ultra-wideband antenna with reconfigurable notched bands

A reconfigurable band-notched ultra-wideband antenna is proposed. The antenna mainly consists of a modified rectangle radiating element, a staircase ground plane and two simple pin diode switches, and its entire size is 33.0×28.0×1.0mm. The presented antenna has nearly omnidirectional patterns, stable gain, small group delay and an available impedance bandwidth ranging from 3.1 to 12.5×GHz, including dual band-notched bands centred at 3.5 and 5.5×GHz, respectively. By reconfiguring the states of pin diode switches, the dual notched bands can be reconfigurable. That is to say, the reconfigurable antenna is able to switch among four operative modes (none or 3.5GHz or 5.5GHz or dual band-rejected).