COPLANAR WAVE-GUIDE-FED UNIPLANAR BOW-TIE ANTENNA

The design of coplanar waveguide (CPW)-fed bow-tie antenna for the 2.4 -GHz ISM band is described in this letter. A coplanar waveguide-to-cop lanar strips (CPW-to-CPS) balun is used to obtain the balanced feed li ne for the printed bow tie. Analysis method based on the mixed potenti al integral equation method is used to characterize the input characte ristics of the bow-tie antenna. Obtained numerical results are in good agreement with experimental data. Through experiments with bow-tie an tennas of various extended angles, the bow-tie antenna with a 90 degre es extended angle exhibits the widest bandwidth in the desired frequen cy band which has a bandwidth of 17% for VSWR <1.5:1.