A Partially Reflecting Surface Antenna With a Non-Resonant Cavity and a Phase-Correcting Surface for Gain Enhancement

Partially reflecting surface (PRS) resonant antennas have attracted significant attention for the past two decades. However, how to improve their peak gain is still a challenge. This article proposes a nonresonant PRS antenna that does not require the conventional resonant condition that limits design flexibility and peak gain. It consists of a PRS, a ground, a small feed, and a transparent phase-correcting surface (PCS) placed above the PRS for phase compensation. The ray-tracing method is used to analyze the proposed nonresonant PRS antenna, and numerical simulations are conducted to verify its effectiveness. Our theoretical and numerical results show that the gain of a PRS antenna with a nonresonant cavity reaches its peak when the cavity height is between
$0.6\lambda $
and
$0.9\lambda $
. Three prototypes are fabricated and tested, and the measured results show that peak gains of over 25 dBi and 3 dB gain bandwidths of more than 10% can be achieved at the same time.