Half‐mode dielectric waveguide antenna fed by a micro‐strip line with air media for endfire radiation

Abstract

A half‐mode dielectric waveguide antenna fed by a micro‐strip line with air media is presented. The proposed antenna consists of two dielectric cuboids and an air‐substrate micro‐strip line. Due to similar modal field configurations, the dielectric cuboids are excited effectively by the micro‐strip line, and they work as two half‐mode waveguide antennas working on the TM0 mode. With the length of 6.5 wavelength at the centre frequency of 5 GHz, a measured endfire gain of 12.2 dBi is achieved. The measured 1 and 3‐dB gain bandwidths could reach 17 and 46%, respectively. Good matching is obtained over the entire operating band from 3.5 to 6.5 GHz. Compared with the antennas mounted on a large conducting plane, the proposed antenna has the advantages of a high endfire gain, a wide endfire gain bandwidth, and a stable endfire radiation pattern.