Compact CPW-fed circular slot antenna for ultra-wideband applications

A compact circular slot antenna for ultra-wideband applications is proposed in this letter. The antenna consists of a circular patch and an open annulus, and is fed by coplanar waveguide. The total dimension of the antenna is 30mm×33mm×1.57mm. The proposed antenna is simulated, fabricated and tested. Results show that a maximum relative impedance bandwidth of more than 130% for |S11| ≪ −10dB can be achieved, covering frequency range of 2.9–13.73GHz, which meets the demand of UWB applications. The effects of the structure parameters on bandwidth are investigated.