A novel millimeter-wave transition fromwaveguide to microstrip line

In this paper, a millimeter-wave transition from waveguide to microstrip is proposed. A rectangular patch element in the short-terminated waveguide is analyzed by the FEM software. The analysis points out that the rectangular patch has optimum sizes which can broad the pass-band of this structure. a prototype transition exhibits an insertion loss of 0.5 dB from 34Ghz to 36GHz, and a bandwidth of 7% for the waveguide port.