The influence of ground and floating planes on the electromagnetic coupling between board tracks

In this paper the electromagnetic field of multiconductor multilayered transmission lines in modern automotive control units is investigated. An integral equation formulation is used to calculate the field distribution and the coupling factor between the microstrip lines. Furthermore the influence of additional ground and floating planes on the coupling factor is discussed and based on the results, basic rules are given that need to be followed when designing EMC/EMI improved layouts. The method is verified and already proven in the industrial application.