Characterization of correlated random Cartesian field components in reverberation chambers using copulas

Realistic operating conditions of reverberation chambers are characterized by nonzero levels of inter- and intra-correlation between Cartesian field components and their I/Q components, giving rise to statistical anisotropy and complex ellipticity (noncircularity) of the random electromagnetic field, respectively. It is shown how empirical copulas for their joint probability distribution function that link the components' marginal distributions can be characterized. The technique is applied to measured data in a reverberation chamber near its lowest usable frequency.