Articles
Crosstalk Effects Of Shielded Twisted Pairs
October 9, 2009
This article deals with the modeling and simulation of shielded twisted pairs with CST CABLE STUDIO™. The quality of braided shields is investigated with respect to perfect solid shields. Crosstalk effects are calculated for unshielded twisted pairs, poorly shielded twisted pairs, and twisted pairs with high-quality shields. Explanations are given how to create realistic simulation setups in order to be able to compare them with measurement results.
Cable Shielding
Shielded cables are widely used in industrial applications in order to suppress unwanted crosstalk effects between neighbouring wires. A typical shielded cable is the coaxial cable with an inner wire and a concentric outer screen.
Ideal shielding conditions can be achieved by realizing the screen as a solid conductor with a specific thickness. With increasing frequency the penetration depth of the electric field decreases until it is less than one half of the shield's thickness. At higher frequencies the current tends to flow mainly on the conductor's surfaces (skin effect), thus completely decoupling the inner part of the screen from the outer part. For a solid screen we can state: the higher the frequency the better the screening.
Click Here To Download:•Application Note: Crosstalk Effects Of Shielded Twisted Pairs
