Wave chaotic characterization of complex cavities: Distributed ports and coupling

A statistical model, the Random Coupling Model, that describes the coupling of radiation into and out of large electrical enclosures is described and generalized. Particular attention is paid to the case in which the ports are electrically large and described by multiple modes (distributed ports). We find a compact expression for a model of the enclosure impedance that can be used to generate probability distributions for fields at the enclosures ports. Coupling of chaotic cavities through localized ports is also analyzed and discussed. In particular, a compact expression for the power coupled through a linear chain of cavities is obtained. It is found that the fluctuation of he coupled signal is governed by a product of independent factors. Results are of interest for weakly coupled (nested) reverberation chambers, arbitrary shaped cavities, and the evaluation of shielding effectiveness in presence of large apertures.