A general waveguide circuit theory

Abstract

This work generalizes and extends the classical circuit theory of electromagnetic waveguides. Unlike the conventional theory, the present formulation applies to all waveguides composed of linear, isotropic material, even those involving lossy conductors and hybrid mode fields, in a fully rigorous way. Special attention is given to distinguishing the traveling waves, constructed with respect to a well-defined characteristic impedance, from a set of pseudo-waves, defined with respect to an arbitrary reference impedance. Matrices characterizing a linear circuit are defined, and relationships among them, some newly discovered, are derived. New ramifications of reciprocity are developed. Measurement of various network parameters is given extensive treatment.

Computationally Efficient Model for Uwb Signal Attenuation Due to Propagation in Tissue for Biomedical Implants

“…These parameters are similar to "power waves" as defined in [22][23][24]. Here they are not referred to as waves because as pointed out in [23] and [24] these parameters differ fundamentally from traveling waves. Still they exhibit power transfer relationships which are useful to this work.…”

“…The impedance η last should be set to the impedance of colon tissue. Plugging these values into (24) results in an accurate calculation of η l (C). This can then be used with (16) and (19) …”

“…In [22], complex load and source impedance are assumed, but as pointed out in [23] an unconventional definition of waves is used which results in Sparameters that are inconsistent with those one would measure on a vector network analyzer. Wave definitions which allow for complex source and load impedances are rigorously defined in [24], but conversions between transmission and scattering matrices as defined in this paper are not given. Thus to avoid confusion, the derivation of (16)-(18) using definitions suitable for this work is included in the Appendix.…”

Scattered Reflections on Scattering Parameters — Demystifying Complex-Referenced S Parameters —

“…This article was derived from an article that I presented at MWE 2015 [44], which, in turn, was based upon a tutorial that I gave in 2011 [45]. Articles that discuss related issues include [4], [17], [46]- [51].…”

“…This arbitrariness implies that there is arbitrariness in the definition of characteristic impedance, too. We don't delve here into the difficult and controversial problem of how the mapping should be done [4]- [8], and simply assume that effective voltage and current have been defined appropriately. We will hereafter refer to them simply as "voltage" and "current," respectively.…”