Low-Dispersive Leaky-Wave Antenna Integrated in Groove Gap Waveguide Technology

In this paper, the use of a dispersive prism with a triangular shape is proposed to reduce the dispersive radiation nature of a leaky-wave antenna (LWA) in groove-gap waveguide technology. The operation of gap waveguide technology is based on the use of metallic pins that act as an artificial magnetic conductor, so the electromagnetic fields are confined and guided in the desired directions. To control a leaky-wave radiation of these confined fields is possible by tailoring the height of the pins, its periodicity, and the waveguide width. This radiation, as in any conventional LWA, is dispersive, leading to beam squint as the frequency is varied. Here, we mitigate this beam squint by using a prism made of dispersive pins and choosing appropriately their periodicity and height. With this prism, the leaky-wave radiation is focused into one single direction in a wide frequency band. This concept is demonstrated with a prototype designed to radiate at phi = 41 degrees with a central frequency of 12 GHz and the high gain of 16.5 dBi. A 22% frequency bandwidth for the 3 dB realized gain at phi = 41 degrees is achieved, and the main radiating direction, with half-power beamwidth of 5 degrees, steers only +/- 0.5 degrees from 11.4 to 13.4 GHz.This work was supported in part by the Alexander von Humboldt Foundation, in part by the Spanish Government under Project TEC2016-79700-C2-2-R, and in part by the Madrid Regional Government under Project S2013/ICE-3000

Review of Low Profile Substrate Integrated Waveguide Cavity Backed Antennas

Low profile cavity backed antennas (CBA) based on substrate integrated waveguide (SIW) technology presented in published papers have been reviewed in this paper. Their operating mechanisms have been discussed and methods for improving the performance, such as bandwidth enhancement, size reduction, and gain improvement, have been presented. These novel antennas retain the advantage of conventional metallic cavity backed antenna, including high gain, high front-to-back ratio, and low cross polarization level, and also keep the advantages of planar antenna including low profile, light weight, low fabrication cost, and easy integration with planar circuit