G-band bowtie dipole antenna

In this paper we propose a 3D micromachined 210 GHz elevated bowtie dipole antenna fed by coplanar waveguide. The antenna is designed for MMICs applications at G-band (140 GHz to 220 GHz). The antenna topology effectively creates a low dielectric substrate and undesired substrate effects can be eliminated, since the antenna substrate is essentially air (the lowest possible dielectric constant) and can be used on most substrates to monolithically integrate. The proposed antenna is composed of coplanar waveguide (CPW) feed line, air-bridges, a feeding post, supporting posts, and a radiator. The elevated antenna is fed with a gold feeding post connected to a CPW line on top of SI-GaAs substrate. The antenna fabrication is based on a standard III-V MMIC airbridge technology. The measured bandwidth is about 8.6 GHz (For return loss<10 dB) from 204 GHz to 212.6 GHz.

I. Introduction

Advanced communication, radar, passive imaging and remote sensing instruments are extending frequency and bandwidth requirements to 200 GHz and beyond. The high frequencies of mm-waves as well as their propagation characteristics make them an excellent choice to satisfy actual requirements imposed by modern wireless communication systems, such as small profile, high data rates, low cost, and short radio links. As is well known, the signal wavelength becomes shorter as the frequency increases, so smaller antennas can be integrated with other circuits. Printed antennas are commonly adopted for these systems since they are light in weight, the low profile, the low in cost, and are easy to fabricate and integrate [1], [2].