Statistical description of shielding problems using multipole analysis

The paper describes the influence of small statistical variations in the physical parameters on the shielding behavior of an enclosure. The varying parameters are given in terms of the first few statistical moments of their distributions. From these the amplitudes of a spherical-multipole expansion are derived analytically. These multipole amplitudes contain the statistical properties of the electromagnetic field valid not only in a single point but in a spherical region around the center of the expansion inside of a shield. Two first examples demonstrate the validity of the approach.