Printed PRS-based Circularly Polarized Resonant Cavity Antenna for mmWave Communications

This paper presents a high-gain, planar, and compact circularly polarized resonant cavity antenna (RCA) with a low profile, designed for mmWave communication systems. The non-uniform electric-field phase distribution across the aperture of the conventional RCAs leads to lower far-field performance. To address this limitation, an array of circular patches is printed on the underside of the partially reflecting surface (PRS) to improve phase uniformity and enhance far-field directive radiation of a classical RCA. This phase correction mechanism results in significant improvements in both directivity and gain. A hexagonal-shaped patch is used as the primary radiating element to excite the cavity and generate circularly polarized waves. A notable performance improvement is achieved in the proposed RCA with a peak gain of 17.91 dBi, peak aperture efficiency of 35.13% at 28 GHz, and a significantly lower side-lobe level in the operating bandwidth.