Three dimensional model based on image theory for low frequency correction factors evaluation in semi-anechoic chambers

The need to study the radiated emissions from electric and electronic devices whose main energy content is below 50 MHz calls for the prediction of correction factors that allows one to correlate the direct electromagnetic field radiated by the device to the total measured field inside a test chamber due to the reflections on all the chamber's walls. A three-dimensional prediction model of these factors, based on the image theory, is developed and validated by comparison with known theoretical results and with measurements. The model simulates both electric and magnetic source dipoles for both polarizations. This model allows a parametric analysis of such factors for different chamber dimensions, relative positions and variation of frequency.