Green´s functions computation of the EMI due to electric dipole sources inside a rectangular cavity

Summary form only given. The EMI of a rectangular enclosure excited by internal electric dipole sources is presented. The interaction between the sources and the enclosure is described by using the dyadic Green´s function. Our detailed approach for electric dipole sources are given in a graphical form. The cavity walls are assumed to be perfect conductors. First a small electric dipole and after an electric dipole with finite length are considered. Closed form expressions for the electric field and the surface current density on the cavity walls are derived. Numerical results for different source positions and different dipole lengths are compared. One of the main conclusion of the results is that the current distribution on the cavity walls is not symmetric and for sources placed away from the cavity walls its maximum is not on the plane normal to the corresponding walls and the source. The effect of multiple dipole sources is found by using the superposition. All the results for two non-resonant frequencies are normalized and show the regions of maximum and minimum EMI. It is pointed out that it is not simple and easy to analyze and design an enclosure containing a series of PCBs. At the time being the mutual coupling of the components of the ICs and microstrips is not taken into account. However it seems that there are some useful and simple rules that can be applied for the PCBs design