Efficient CAD Tool for Inductively Coupled Rectangular Waveguide Filters with Rounded Corners

The `rounded corners' effect is commonly introduced during the fabrication step of passive devices in rectangular waveguide technology. Recently, several methods have been proposed for considering such effect in the H- and E-plane of cavity filters. In this paper, the presence of rounded corners in the cross-sections of inductively coupled filters is successfully solved following a novel hybrid technique. Furthermore, a complete automated design procedure based on this new analysis technique is fully detailed. Following this new design technique, a WR-90 waveguide filter considering rounded corners in the cross-section of the cavities and coupling windows has been obtained.