A broadband 140 GHz aperture-coupled SPA Antenna in LTCC-Technology

With this work, an aperture-coupled stacked patch array antenna (SPA) in Low Temperature Cofired Ceramic (LTCC) technology for use in the D-band (110 GHz to 170 GHz) is presented. The antenna is designed for a miniaturized broadband Antenna-in-Package application. For the antenna Ferro material A6M-E with relative permittivity of 5.8 and minimal tape thickness of 50 μm was used. The antenna physical features contributing to the coupled resonances include a grounded-coplanar-waveguide to microstrip transition feedline, a rectangular aperture, two stacked patch layer and a via fence resulting at a size of approx. 30 mm$^{2}$. For enhanced beamforming purposes, a miniaturized, elliptical lens was custom-made to cooperate with the antenna. Performance measurements, as well as comparisons with previous simulation results will be presented. The measured reflection coefficient and far-field radiation pattern of the manufactured LTCC antenna shows excellent agreement with the simulation results.