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A Logarithmic Version of the Complex Generalized Smith Chart

By Pablo Vidal-Garcia and Emilio Gago-Ribas
Progress In Electromagnetics Research Letters, Vol. 68, 53-58, 2017


Based on the complex analysis of the Lossy Transmission Line Theory, which involves the result of a Generalized Smith Chart, a new version of the last one arises when trying to characterize the wave impedance along the Transmission Line by means of analytical complex functions. Among these functions, the complex logarithm of the reflection coefficient leads to the logarithmic-reflexion coefficient-plane and its parameterized version, the Logarithmic Generalized Smith Chart. This plane is specially useful for characterizing the Transmission Line along its extension. To validate these results, some examples will be presented providing physical interpretations to the behaviour of a lossy TL and pointing out some practical applications.


Pablo Vidal-Garcia and Emilio Gago-Ribas, "A Logarithmic Version of the Complex Generalized Smith Chart," Progress In Electromagnetics Research Letters, Vol. 68, 53-58, 2017.


    1. Gago-Ribas, E., Complex Transmission Line Analysis Handbook, Vol. GW-I, ``Electromagnetics & Signal Theory Notebooks" series. GR-Editores, Leon, Spain, 2001.

    2. Gago-Ribas, E., P. Vidal-Garcia, and J. Heredia-Juesas, "Complex analysis and parameterization of the lossy transmission line theory and its application to solve related physical problems," International Conference on Electromagnetics in Advanced Applications, ICEAA 2015 Proceedings, 141-144, Torino, Italia, September 7-11, 2015.

    3. Smith, P. H., "Transmission-line calculator," Electronics, Vol. 12, 29, 1939.

    4. Smith, P. H., "An improved transmission-line calculator," Electronics, Vol. 17, 130, 1944.

    5. Gago-Ribas, E., C. Dehesa Martinez, and M. J. Gonzalez Morales, "Complex analysis of the lossy-transmission line theory: A generalized Smith Chart," Turkish Journal of Electrical Engineering & Computer Sciences (Elektrik), Special issue on Electrical and Computer Engineering Education in the 21st Century; Issues, Perspectives and Challenges, Turkey, Vol. 14, No. 1, 173-194, 2006.

    6. Wu, Y., Y. Zhang, and Y. Liu, "Analysis of the omnipotent Smith Chart with imaginary characteristic impedances," ICMMT 2008 Proceedings, Nanjing, China, April 2014.

    7. Wu, Y., H. Huang, and Y. Liu, "An extended omnipotent Smith Chart with active parameters," Microwave and Optical Technology Letters, Vol. 50, No. 4, 896-899, 2008.