An Optimal New Shielded Twisted Pair Model to Improve the Electromagnetic Immunity in the Automotive Applications

Shielding twisted pair with metallic tape is a widely used resource to reduce the electromagnetic emissions and increase noise immunity of the twisted pair to those emissions. But, in addition to decrease electromagnetic emissions, shield also affects electric and geometry characteristics of the pair. Estimation of twisted pair geometry is vital to compute as much as the shield affects the electric characteristics of the pair. The goal of this paper is to develop a model of shielded twisted pair which allows to compute the shield shape as a function of twisted properties of the pair and physical characteristics of the shield tape. The model calculated in this paper is a part of a large work research; with the results of that research we can calculate the most used electric characteristics of the pair according to the physical and geometrical characteristics of it. This research was applied in an important cable manufacturing company of the automotive sector.