Circularly Polarized Millimeter-Wave Antenna Using 0-Level Packaging

This letter presents a 60-GHz millimeter-wave antenna fabricated with a wafer-scale packaging technology. A feeding network is designed in a coplanar waveguide (CPW)-fed aperture on GaAs substrate. The radiating patch is realized in a 0-level packaging cavity using a glass substrate with a low dielectric constant. The circular polarization is achieved by an inclined coupling slot to the boundary of the square radiating patch. A 45° inclination enables the splitting of the dominant resonant mode into two near-degenerate orthogonal modes for circular polarization radiation. A finite-element-method (FEM)-based 3-D full-wave electromagnetic solver, CST Microwave Studio, is used for the design simulations. Typical numerical simulations and experimental results of the antenna performance are presented and discussed.