Occurrences of Received Power Anomalous Statistics in Reverberation Chamber

In this paper, we present and improve a broadband statistical analysis of anomalous occurrences inside an electromagnetic reverberation chamber. Besides the traditional Anderson-Darling (AD) test, used as a statistical metric for the distance between theoretical and experimental distributions, we introduce the Pearson system, able to assign a distribution family by knowledge of the first two scale invariants, namely skewness and kurtosis. It is shown that such a system can be used as a test to detect departures of idealized statistics for random fields. In particular, while the AD test is sensitive to low part distortions (as opposite to low values of the support) of the DF, i.e., rejects hypothesis, the Pearson category changes whether right tail is far apart. As a particular case, when both the tests flag out a departure, measured distribution is completely different from the asymptotic one. Upon analysis of the received power, it is found that overmoded regime follows a Pearson type I (beta) or type VI (beta prime) distribution, while undermoded and anomalous occurrences follow a Pearson type IV distribution. This corresponds to a right tail departure and is physically explained by the presence of higher-order coherency, recently predicted by theory.