Coupling in the Far-field — Lesson 4

This lesson covers the concept of crosstalk or near field coupling in shielded cables. It delves into the analysis of crosstalk in single core shielded wire cables, using low frequency analysis. The lesson explains the generic models for inductive and capacitive coupling and how these principles are applied in the analysis of crosstalk. It also discusses the equivalent circuits for analysis of capacitive and inductive crosstalk. The lesson further elaborates on the impact of shield properties and frequency on the reduction of inductive crosstalk. It concludes with an explanation of how shielding can be used to prevent radiated emission.

Video Highlights

00:12 - Different types of shielded cables and their applications
05:17 - Shielded cables - situation
11:22 - Shielded cables - capacitive coupling
16:52 - Shielded cables - inductive coupling
22:06 - Shield cut-off frequency and its implications
28:42 - How shielding can prevent radiated emission

Key Takeaways

- Crosstalk in shielded cables can be analyzed using the principles of inductive and capacitive coupling.
- The equivalent circuits for capacitive and inductive crosstalk help in understanding the phenomenon better.
- The properties of the shield and the frequency play a crucial role in reducing inductive crosstalk.
- Shielding can be effectively used to prevent radiated emission.
- The shield should be connected to the ground at both ends to eliminate inductive crosstalk and at least one end to eliminate capacitive crosstalk.