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A Complete Multimode Equivalent-Circuit Theory for Electrical Design



Dylan F. Williams, L. A. Hayden, Roger Marks


This work presents a complete equivalent-circuit theory for lossy multimode transmission lines. Its voltages and currents are based on general linear combinations of standard normalized modal voltages and currents. The theory includes new expressions for transmission line impedance matrices, symmetry and lossless conditions, source representations, and the thermal noise of passive multiports.
Journal of Research (NIST JRES) -


conductor current, conductor representation, conductor voltage, electromagnetic modes, impedance matrix, modal representation, multiconductor transmission line


Williams, D. , Hayden, L. and Marks, R. (1999), A Complete Multimode Equivalent-Circuit Theory for Electrical Design, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed June 24, 2024)


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Created June 22, 1999, Updated February 19, 2017