Broadwall-Side Stripline-to-Waveguide Transition

A novel microstrip to metallic rectangular waveguide transition is presented in this paper. Unlike other proposed transitions, in this design, the PCB microstrip circuit does not extend into the waveguide from any side, and no tuning is used inside the waveguide. The PCB microstrip circuit is simply placed on top of the waveguide, along its broadwall side. And using a slot opening in the broadwall side, the field is injected from/to the waveguide. In addition to its simplicity and small size, this approach makes the new design very attractive for lower cost volume production. Another new feature of this novel design is that it also functions as a 1:2 power divider, which makes it an ideal component for designing compact beam forming networks for array antenna applications. For applications with small bandwidth requirements, this paper demonstrates a unique approach to reducing the size of the transition, without jeopardizing the resonant frequency of the transition.