A Comparative Analysis of UWB Phased Arrays With Combining Network for Wireless-Power-Transfer Applications

This article presents the theory, design, and demonstration of the performance of multiple ultrawideband and low-profile modified microstrip line-based phased array antennas with
$4 \times 4$
and
$6 \times 6$
quadrants. A comparative analysis of the performance between the novel combining network-based
$4 \times 4$
and
$6 \times 6$
phased antenna arrays is demonstrated in terms of dimension, gain, half-power beamwidth (HPBW), and beam steering capability. The proposed combining network is an attractive solution for wide-angle scanning phased array antennas because the diagonally connected elements of the network have achieved an additional 45° phase difference. The measured peak gains for the
$4 \times 4$
and
$6 \times 6$
antenna arrays are 15.5 and 24.39 dBi, respectively, while achieving an
$S_{11} < -35$
dB. The
$4 \times 4$
array achieves a bandwidth (BW) of 0.69 GHz (6.42–7.11 GHz, fractional BW (FBW) of 10.19%), while the
$6 \times 6$
array achieves 1.67 GHz BW (8.93–10.60 GHz, 17.10% FBW). The measured radiation patterns of the
$4 \times 4$
and
$6 \times 6$
antenna arrays show the beam steering range of - 13° to 99° and - 9° to - 81°, and - 150° to 30° and - 15° to 45° along the
$\phi $
- and
$\theta $
-axes at 6.69 GHz and - 52° to 31° and - 36° to 45° along the
$\phi $
-axis at 10.34 GHz, respectively. The results demonstrate that the suggested antenna arrays are promising candidates for unmanned aerial system (UAS)-based wireless-power-transfer (WPT) applications.