155 GHz Dual-Polarized Fabry-Perot Cavity Antenna Using LTCC-Based Feeding Source and Phase-Shifting Surface

This communication introduces a design of a dual-polarized Fabry-Perot cavity (FPC) antenna operated at the D-band. A novel phase-shifting surface (PSS) made of a single dielectric material based on the low-temperature cofired ceramic (LTCC) technology is applied to this antenna. The proposed PSS functions as a partially reflective surface (PRS) with a transverse permittivity gradient (TPG), contributing to a directive beam radiation. A dual-polarized LTCC-based feeding source with bandwidth enhancement is designed to feed the cavity. For verification, a dual-polarized LTCC FPC antenna prototype operating at 155 GHz was designed, fabricated, and measured. It consists of the feeding source, the PSS, and a 3-D printed supporter. The measured peak gains of the horizontal and vertical polarizations are 17.5 and 17.1 dBi, respectively. The overlapped impedance bandwidth for both the polarizations is 10.4%. These performances ensure that the proposed dual-polarized LTCC antenna is a promising candidate for D-band applications.