A CPW-fed bow-tie slot antenna with tuning stub

In this paper, a modified slot bow-tie antenna fed by a coplanar waveguide (CPW) is investigated for wideband operation. It is designed to work on a thin substrate (h = 0.787 mm) with a low dielectric constant (epsiv
_r
= 2.2) operating at two frequencies (1.8 and 2.4 GHz). Two metal stubs are introduced in the middle of the bow-tie slot in order to achieve a wider impedance bandwidth over the conventional CPW-fed bow-tie slot antenna. The antenna is fabricated and tested in the antenna measurement facility of UCL and experimental far-field results are presented showing low cross-polarisation levels. The bow-tie slot antenna can obtain at least 55% bandwidth.