The emission from transmission lines plays an important role in theelectromagnetic compatibility of automotive electronic systems. In afrequency range below 200 MHz radiation from cables is often the dominantemission factor. In higher frequency ranges radiation from PCBs and theirhousing becomes more relevant. Main sources for this emission are theconducting traces. The established field measurement methods according CISPR25 for evaluation of emissions suffer from the need to use large anechoicchambers. Furthermore measurement data can not be used for simulation modelcreation in order to compute the overall fields radiated from a car. In thispaper a method to determine the far-fields and a simulation model ofradiating transmission lines, esp. cable bundles and conducting traces onplanar structures, is proposed. The method measures the electromagneticnear-field above the test object. Measurements are done in time domain inorder to get phase information and to reduce measurement time. On the basisof near-field data equivalent source identification can be done. Consideringcorrelations between sources along each conductive structure in modelcreation process, the model accuracy increases and computational costs can bereduced.
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