A tapered long slot antenna of conical radiation beam based on substrate integrated waveguide

In this paper, a long slot antenna of conical radiation beam is presented, which is based on the substrate integrated waveguide (SIW). The antenna consists of a pair of tapered long slots etched out of both the top and bottom broad walls of a substrate integrated waveguide to produce the conical radiation beam. Experiment results of the fabricated antenna show that the realized beam-pointing angle is 55.2° and its maximum realized gain is 12 dB with a ripple of 3.5 dB in the E-plane at the operating frequency of 15 GHz. The 10 dB return loss bandwidth is 29.3%, from 13.6 GHz to 18 GHz.