Narrow wall axial-slot-coupled T junction between rectangular and circular waveguides

An analysis is presented of a T junction between rectangular and circular waveguides coupled through a long axial slot in the narrow wall of the rectangular waveguide. A moment method with entire orthogonal basis functions is used for deriving expressions for the elements of the scattering matrix. The effect of the wall thickness is taken into account by treating the coupling slot as a short section of a rectangular waveguide and matching the boundary conditions at the interfaces. The conditions satisfied by the scattering matrix of the junction are verified. A comparison between theoretical and experimental results on variation of coupling with frequency is presented.<
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