Predicting the maximum radiated electric field strength from unintentional radiators

The measurement procedures to determine the maximum emissions of electronic devices are described in different standards by CISPR. However, these standards only account for testing the equipment under test (EUT) while assuming that the engineer knows the direction corresponding to the highest level of emission. But, electronic devices act as unintentional radiators. This means that it is not possible to know the direction of maximum emission a priori without performing a complete 3-dimensional scan which is very time-consuming. In this paper, a stochastic approach for the maximum directivity of unintentional radiators is used to predict the maximum emissions from reduced sampling assumptions. This approach is applied to the simulation results of a generic EUT by the use of the software FEKO.