Design and experiments of 77 GHz antennas in LTCC technology

The design of a slot coupled microstrip patch antenna with four parasitic elements for the 77 GHz frequency range is presented. Full wave electromagnetic simulations were used for antenna modeling and optimization. The antenna was fabricated using Ferro A6-M Low Temperature Co-fired Ceramic technology. The “on wafer” measurements showed a central operating frequency of 78 GHz with reflection losses of -19 dB. The frequency bandwidth (defined for reflection losses lower than -10 dB) was from 76.4 GHz to 79.3 GHz. Using electromagnetic simulations based parametric study it is demonstrated that the central frequency shift is mainly due to the fabrication tolerances that affect the active patch dimensions.