Wideband aperture coupled stacked patch type microstrip to waveguide transition for V-band

A compact aperture coupled patch type microstrip-to-waveguide transition at V-band is proposed and fabricated using LTCC(Low Temperature Co-fired Ceramic) process. It uses the aperture coupled microstrip feed and the parasitic patch antenna radiating into the waveguide to improve the insertion loss and the bandwidth. As a result of experiments, low transmission loss and high return loss are realized at the design frequency of 60 GHz. For a 10 dB return loss, a relative bandwidth of 13.8% is obtained for a fabricated back to back transition.