Comprehensive and Practical Way to Look at Far-End Crosstalk for Transmission Lines with Lossy Conductor and Dielectric


Far-end crosstalk (FEXT) noise is one of the major issues that limits signal integrity performance for high-speed digital products. It is important to estimate the crosstalk noise accurately to avoid noise margin failure or overdesigned transmission lines. Traditionally, analytical formulas for crosstalk noise are based on lossless and perfect impedance match assumptions, which provide limited guidance for a practical high-speed transmission line design. A phenomenon is observed that a lossy conductor increases the FEXT on coupled striplines. To provide a reasonable explanation, analytical and numerical investigations were performed using a modal analysis based approach. A new FEXT component due to the lossy conductor is proposed. Such FEXT component is important to a high-speed stripline design because it is a major contributor when all terminals are matched. To estimate the impact of loss on FEXT, a practical and fast estimation approach is proposed.


Electrical and Computer Engineering

Research Center/Lab(s)

Electromagnetic Compatibility (EMC) Laboratory


This work was supported in part by the National Science Foundation under Grant IIP-1440110.

Keywords and Phrases

Far-End Crosstalk (FEXT); Lossy Conductor; Proximity Effect; Serializer/Deserializer (SerDes); Transmission Line Theory

International Standard Serial Number (ISSN)


Document Type

Article - Journal

Document Version


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© 2020 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Apr 2020