A High-Efficiency Circularly-Polarized Aperture Array Antenna with a Corporate-Feed Circuit in the 60 GHz Band

摘要

A circularly-polarized planar array antenna using hexagonal aperture elements is proposed. A 2 × 2-element subarray as the basic unit is excited by a corporate-feed circuit located in the lower layer of the double-layered antenna. The hexagonal aperture is designed to achieve a good axial ratio in the boresight. A 16 × 16-element array antenna with uniform element spacing smaller than the free-space wavelength was fabricated by diffusion bonding of laminated thin metal plates for the 60 GHz-band. The high gain of 33.4 dBic is measured with 91.6% antenna efficiency, including losses.