Spectral analysis of random digital signals

The spectral analysis of random digital signals represents an important issue to understand the EMC performance of equipment and systems. Wold´s theorem allows to get a better insight into the spectral structure of the emitted signal. On the basis of the basic principles of this theorem the spectral components of the random digitals are calculated and identified. Using the properties of adaptive filters a technique to separate the predictable (narrowband) and regular (broadband) spectral components is illustrated.