V.V. Zemlyakov

Band-pass filters are widely used in waveguide technologies for selective devices design. The selective devices design based on waveguides of complex cross-section is of great practical interest and could be a perspective investigation because such waveguides, for example ridge-, double ridge-, cross-guides, offers much advantages, specifically better range and mass performances, low losses in comparison with traditional waveguides (circular and rectangular). In this paper the electrodynamics analysis and synthesis of band-pass filters on single- and double-ridged waveguide with evanescent-mode rectangular waveguides as impedance inverters are described. Electromagnetic fields and cutoff wave numbers of propagating and non propagating TE and TM waves are calculated by method of partial regions including field singularities at the edge. In calculation of multimode scattering matrix the interaction of irregularities by higher order non propagating modes is included. The calculation results of S-parameters of synthesized broadband filters on single- and double-ridged waveguides are shown. The comparison of calculation results with the results of computer simulation by numerical techniques confirms the efficiency of developed algorithms.