The design of Ka band waveguide-to-microstrip transition

This paper describes the theory and design method of waveguide-to-microstrip transition. As an example, a Ka band rectangular waveguide-to-microstrip transition is designed. Using the ANSOFT HFSS EDA tool, this transition is simulated, optimized. For convenience, a back-to-back structure with two this kind transitions is implemented and tested. The measured insertion loss of the back-to-back construction is lower than 0.9dB at 35.5GHz. The insertion loss of a single transition is therefore about 0.45dB. The input and output reflection coefficients measured are smaller than -20dB. All the measured date show good agreement with the simulated ones.