Study and Design of Broadband Bow-tie Slot Antenna Fed With Asymmetric CPW

In this communication, a new style of broadband bow-tie slot antenna with an improved gain is presented. It is fed by an asymmetric coplanar waveguide (ACPW) with different slot lengths. By adjusting the length of one ACPW slot, the impedance characteristic of the antenna is greatly improved so that the bandwidth is broadened. Meanwhile, to improve the gain at low frequency band, a loop strip is added in the bow-tie slot. The simulated and measured results show that the proposed antenna can operate from 2.76 GHz to 8.1 GHz and the relative bandwidth is 100.4%. Furthermore, the flatter gain within the operating frequency band is obtained and the maximum gain at beam peak reaches 5.53 dBi.