Research On Crosstalk Prediction Of Automotive Electronics Transmission Lines

With the rapid development of automobile industry, the electronic control systemused in vehicles is also increasing. This transformation will be open up broader spacefor the future development of automotive industry. Although the automobile electronicdevices convenient the user’s operation, it also brings new challenges to theautomotive electromagnetic environment where space is limited, especially theelectromagnetic interference problem caused by the large number of transmissionlines. This electromagnetic interference will effect the operation accuracy ofautomobile electronic system, while the system automatically misoperation willendanger life safety. These hazards are also the important reasons for assurance thatoverall systems should be meet electromagnetic compatibility at automotive R&Dprophase. As transmission lines crosstalk problems dominates automobileelectromagnetic interference, this paper research and establish a transmission linecrosstalk prediction model of automobile electronic system through based on thetransmission line theory. And do some fruitful work for automobile preliminarytransmission lines crosstalk test.According to the transmission line crosstalk theory, the existence of wireparasitic parameters is the main cause of crosstalk, on this basis, put forward usingmirror image method to get the distributed parameter values of the unit length. Hereincluding uniform and non-uniform two tapes of wire. After compared with EMCstudio simulation values, the accuracy of the model was obviously.After get the unit length distribution parameter values, transmission linescrosstalk model was built from the aspects of double and three conductor transmissionlines. The terminal voltage was regarded as the research target, categorized all thewires through the rule of different tape transmission line have different propagationvelocity. The same category wires was regarded as one mode, and each model can beviewed as an independent homogeneous medium transmission line system, after thedefinition that different mode have different propagation constant, then integrates allmodes of wave equations through the propagation constants, and obtain the wholecrosstalk voltage values. At the same time, use the same parameter values dosimulation in the EMC studio. The high degree of coincidence results illustrates the theoretical feasibility of the model.Based on the theoretical foundation, analysis of the different important modelparameters influence on the proximal and distal crosstalk voltage, combined withpractical application, put forward a number of specific measures to effectively reducethe transmission lines crosstalk.In order to make the model more practical, establish a test bench mainly aimed atshielding transmission lines. And observe the effects of important parameters on thecrosstalk. Through the experimental data and the calculation results of the modelcomparison chart diagram, good consistency is given illustrated the effectiveness ofthe crosstalk estimation model. This kind of method based on model theory applied tothe automobile development preliminary electromagnetic compatibility testing, notonly can simplify the experiment process, but also will greatly reduce the cost.