Dispersive characteristics of a waveguide with wide impedance walls

Some questions of implementation of concept of a surface impedance for studying dispersive characteristics of a rectangular waveguide with impedance wide walls are examined in the present article. Practical value of the results is determined by simplicity and possibility to use the applied method of studying the electromagnetic fields in waveguide connections with holes of coupling with complicated configuration. This approach is used on an example of absorbing filter of harmonics representing a complicated connection of a rectangular and round waveguides joined through the holes of coupling on a wide wall.