Miniaturization circular wide slot ultra wideband antenna with X-band rejection filter function

A CPW-fed ultra-wideband monopole antenna with X-band rejection filter characteristic is proposed. The proposed rejection filter is obtained by using a stepped impedance resonator (SIR) with inner stub embedded in the CPW fed transmission signal line. The center frequency of the notch band can be controlled by adjusting the dimensions of the stepped impedance resonator and its inner stub. The proposed UWB antenna without SIR also has an impedance bandwidth of 131%. The antenna was designed, simulated and measured successfully. Experimental and numerical results show that the proposed antenna with compact size of 32×24mm², has an impedance bandwidth range from 2.8GHz to 13.5GHz for voltage standing-wave ratio less than 2, expect the notch band frequency 8.2GHz-9.4GHz for X-band communication applications.