Substrate Integrated Waveguide Cavity-Backed Wide Slot Antenna for 60-GHz Bands

Abstract

A wide slot antenna backed by a substrate integrated waveguide (SIW) cavity is presented and investigated for the enhancement of operating bandwidth at 60-GHz band. The 10-dB return loss impedance bandwidth of the antenna increases from 3% to 11.6% with consistent radiation performance as the width to length ratio (WLR) of the rectangular slot cutting from the SIW increases from 0.12 to 0.71. Its dual-resonance operation mechanism is verified by a parametric study. Three 2 × 4 antenna arrays with different slot WLRs are designed and fabricated with a printed circuit board (PCB) process at the 60-GHz bands. The measured results show that the antenna array with slot WLR of 0.71 achieves the gain of 10-12 dBi and the cross-polarization levels of better than 25 dB in both <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">E</i> - and <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">H</i> -planes over the enhanced operating bandwidth of about 11.6%.