Analysis of inductive multiport microwave devices employing a novel double parallel plate approach

The authors present a novel surface integral equation approach to analyse inductive microwave devices with several parallel input-output ports containing inductive metallic and dielectric obstacles. The technique decomposes the main problem into three subproblems, employing different kinds of Green's functions. One of the subproblems uses the classical Green's functions of an infinite unbounded medium with the constitutive parameters of the dielectric obstacles. A novel point of the technique is the formulation of the two other subproblems with two different, 90° rotated parallel plate regions. In these regions the parallel plate waveguide Green's functions are used to simplify the modelling of the excitation problem. The second novel aspect of the work is in the treatment of these Green's functions, to smooth their behaviour, and to improve their convergence. Several numerical results are presented to demonstrate the usefulness of the algorithms proposed. Also, several results for inductive microwave devices are presented to show the practical value of the approach.