Waveguide Discontinuities and Components

The author’s preferred method of treatment of waveguide discontinuities is the modal theory of diffraction of waves, which gives a clear understanding of this effect. From an educational point of view, this technique is essential to form the physics-based knowledge of the phenomena. The modes in waveguides are associated with the equivalent transmission lines, and the one-modal approximation is used widely in MW techniques. The multi-modal representation of the diffracted fields requires matching modes at the discontinuities. The integral and stationary functional methods are to obtain the equivalent circuit models of discontinuities. This idea, related to the waveguide theory’s founders, can be used to interpret the results obtained by those numerical methods. There are 37 references and seven figures.