CAD of evanescent-mode bandpass filters based on the short ridged waveguide sections

The paper presents the internal details of a developed full‐wave algorithm for the computer‐aided design of evanescent‐mode bandpass filters formed by single‐ or double‐short ridged waveguide sections. New filter configurations with an enlarged cross section of filter housing and nonconventional notch‐strip‐notch elements providing improved stopband performance are given special considerations. Additional input–output transformers built on rectangular waveguide sections are used in designing broadband filters. Characteristics of one of the designed filters are verified by measured data. © 2001 John Wiley & Sons, Inc. Int J RF and Microwave CAE 11: 354–365, 2001