Waveguide-to-Microstrip Antipodal Finline Transition at W Band

This paper researched the waveguide-to-microstrip antipodal finline transition at W band, analyzed and simulated antipodal finline transition of Cosine-squared taper function curve and flexible spline curve, designed and fabricated an spline curve antipodal finline transition of back-to-back structure. The measured results show that the insertion loss is less than 1.3dB, and the return loss is less than -13dB in whole W-band, the insertion loss of a single transition is less than 1.0dB, and the return loss is less than -20dB in 90GHz~ 99GHz, achieve good performance. It can provide low transitions between the wave guide and micro strip line. It is loss easy designing and machining, it achieve good performance in a wide band range. It is useful to design circuit in W-band.