Hybrid Waveguide Structure Research Articles

Circuit modeling of general hybrid uniform waveguide structures in chiral anisotropic inhomogeneous media

A new generalized high-frequency transmission line model is presented for general uniform hybrid waveguide structures consisting of inhomogeneous isotropic oranisotropic media. Starting from Maxwell's equations, the generalized coupled telegrapher's equations are found and the frequency-dependent transmission line parameter matricesR(ω),G(ω),L(ω), andC(ω) are defined in an unambiguous way as integral expressions of the normalized electromagnetic fields over the cross section of the structure. Some examples illustrate this general circuit-oriented modeling approach. In the appendix we also present a new extended high-frequency circuit model for general uniform hybrid waveguide structures consisting ofchiral anisotropic inhomogeneous media.

New reciprocal circuit model for lossy waveguide structures based on the orthogonality of the eigenmodes

In this contribution, we present a new consistent equivalent transmission line model to describe the propagation along lossy hybrid waveguide structures. All existing consistent transmission line models are based on the assumption that the power propagated by the modes considered in the waveguide is the same as the power propagated in the model. In a lossy reciprocal waveguide, this leads to a nonreciprocal transmission line model because the modes are not power orthogonal. We start from the Lorentz orthogonality condition to construct a reciprocal transmission line model, even for lossy waveguides. For multiconductor waveguides, we discuss what we call RI-and RV-models, in analogy with the existing PI- and PV-models. We also present a generalisation of these RI- and RV-models to general waveguide structures. The theory is illustrated with a comparison of an RI- and PI-model for a lossy thick microstrip structure. >