122 GHz aperture-coupled stacked patch microstrip antenna in LTCC technology

An aperture-coupled stacked patch microstrip antenna based on Low-Temperature Co-fired Ceramic (LTCC) technology is presented in this paper. Inspite of using an antenna substrate with high permittivity of 7.1 and only 200 µm thickness, wide bandwidth characteristic is achieved by means of coupled resonances. The antenna physical features contributing to the coupled resonances include a rectangular aperture, two stacked patches and a double via fence. The influence of various antenna parameters is analyzed in order to optimize the antenna design. The measured antenna reflection coefficient and gain shows good agreement with the simulation results, thus verifying the future potential for integrating this off-chip antenna with a Millimeter-Wave Integrated Circuit (MMIC) placed in an LTCC air cavity, for realization of a 122 GHz fully integrated, low-cost and surface mountable LTCC Antenna-in-Package.