A Comprehensive and Practical Way to Look at Crosstalk for Transmission Lines with Mismatched Terminals


The analytical formulas for crosstalk due to backward and forward coupling were originally introduced in 1963 [1]. In 2016, the formulas were extended for asymmetrical traces [2]. But all previous approaches assume perfectly-matched terminals, which limits the usage of these equations. In this paper, we re-define the far-end crosstalk (FEXT) as a combination of several components generated by different coupling and reflection mechanisms. A new set of crosstalk estimation formulas is developed to calculate the contribution of each component. Because the influence of mismatched terminals is introduced, the proposed method has much better accuracy than the traditional approach, which estimates FEXT by using forward coupling noise alone. In addition, the proposed equations use per-unit-length inductance (L) and capacitance (C) metrics as inputs instead of S-parameters. Since L and C can be calculated using analytical formulas, the new approach provides a practical and fast crosstalk estimation for engineering designs, avoiding the time-consuming numerical full wave 2D or 3D simulations.

Meeting Name

2018 IEEE Symposium on Electromagnetic Compatibility, Signal Integrity and Power Integrity, EMC, SI and PI 2018 (2018: Jul. 30-Aug. 3, Long Beach, CA)


Electrical and Computer Engineering

Research Center/Lab(s)

Electromagnetic Compatibility (EMC) Laboratory

Keywords and Phrases

Busbars; Electromagnetic compatibility; Scattering parameters, Analytical formulas; Cross-talk Estimation; Engineering design; Far end crosstalk; Perfectly matched; Reflection mechanism; Telegrapher equation; Traditional approaches, Crosstalk

International Standard Book Number (ISBN)


Document Type

Article - Conference proceedings

Document Version


File Type





© 2018 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Aug 2018