Development of Low Profile Substrate Integrated Waveguide Horn Antenna with Improved Gain

Abstract

In this paper, a new low profile Substrate Integrated Waveguide (SIW) probe-fed H-plane horn antenna<br><br>with improved gain is proposed. It consists of two waveguides, including a rectangular and a tapered<br><br>one, in which both the first and third modes of the structure are simultaneously excited leading to<br><br>a uniform field distribution along the radiating aperture of the antenna and in turn, its directivity is<br><br>improved. Moreover, using a coaxial probe to excite the antenna, spurious radiation due to the feeding<br><br>network is suppressed. The antenna structure is numerically analyzed using a software package, and a<br><br>prototype is made using a single thin substrate layer. A good agreement is obtained between simulated<br><br>and measured results. The measured results show 10.48 dBi gain which is 4.9 dBi higher than the gain<br><br>of a conventional SIW horn obtained at 27.8 GHz. The introduced antenna is compact and can be used<br><br>as a single antenna or as an element of a large antenna array.