Source stirring analysis in a reverberation chamber based on modal expansion of the electric field

In this article, a numerical model based on a physically accurate combination of the cavity modes of a reverberation chamber is presented. This new model allows to compute the E-field in the reverberation chamber volume and to get the magnitude coefficient of every excited mode for a given transmitter position. These mode coefficients give a precious information on how the modes are combined in the cavity when a transmitter is moving (source stirring). Then, we try to find a relation between the number of independent source positions and the number of modes excited in the cavity during the source stirring process. Different source stirring configurations are studied and discussed in comparison with mechanical stirring. Future usages of this numerical model are discussed.