Random coupling model for the radiation of statistical sources inside cavities

We review a statistical model, the random coupling model, that describes the high-frequency excitation of irregular cavities through arbitrary sources. The model uses wave chaos theory to describing wave mixing in terms of universal fluctuation laws. The model accounts for system specific details of the excitation through a deterministic description. We consider the scenario where a continuous statistical source operates inside an irregular cavity with losses. Discrete approximations of complex sources in terms of dipoles are available in literature. This can be exploited to construct an impedance matrix at the terminals (ports) of the dipole, and thus characterise the response of the cavity in therms of voltages and currents. In particular, upon a random current excitation, conveniently characterised in terms of correlation matrix, an ensemble average voltage-voltage correlation matrix can be found through the impedance matrices predicted by the random coupling model. Results are of interest in electromagnetic compatibility for the characterisation of multifunctional digital electronics, as well as for dense multiple-input multiple-output communication operating in reflecting environments.