A Wideband Fabry–Perot Cavity Antenna With Single-Layer Partially Reflective Surface

Abstract

A gain-stabilized broadband Fabry–Perot cavity antenna (FPCA) is presented, based on a single-layer partially reflective surface (PRS). The proposed PRS employs compact double-sided structure in a regular hexagonal arrangement to achieve a wide range of positive phase gradient from 7.9 to 10.9 GHz. The PRS unit is composed of a circular patch and a fan-shaped tripod within a circular aperture, which printed on both sides of the thin dielectric substrate. A slot antenna with nonuniform parasitic patches is applied as the source antenna of the FPCA, which provides a smooth gain while offering a wide impedance bandwidth. Simulation and measurement results verify that the PRS can effectively improve the performance of the FPCA in terms of widening the bandwidth, reducing the size, and improving the gain stability. The proposed antenna has a measured 3 dB gain bandwidth of 7.9–11 GHz (32.8%) with a peak gain of 13.67 dBi, and an overall size of 2.1 × 2.1 × 0.57 <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">λ</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">λ</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> being wavelength at the center frequency of 9.5 GHz).