Design of High-Gain Cavity-Backed Planar Spiral Antenna Based on Arc-Shaped Metasurface

A high-gain cavity-backed planar spiral antenna based on arc-shaped metasurface (ASM) is proposed and designed. The unidirectional beam of the Archimedean planar spiral antenna (ASA) is achieved by loading the
$\lambda/4$
-distance metal reflector back cavity. A metasurface consisted of arc-shaped unit cells is located at 28mm above the spiral. The simulated results indicate that the impedance bandwidth of the proposed antenna is 4.53-8.29GHz and the axial ratio bandwidth of 3dB is 5.33-8.29GHz. The gain of the cavity-backed planar spiral antenna is increased by dBi in the frequency band 4.5-6.25GHz due to the proposed ASM, and the proposed antenna presents a peak gain of 12.67 dBi at 5.5GHz.