A proficiency test through interlaboratory comparison of radiated emission measurements was carried out in the period of time comprised between May 2012 and May 2013. Nineteen test houses took part in the exercise providing 91 measurement results in total. Measurements were performed in anechoic chambers and in the frequency range comprised between 200 and 3000 MHz. A traveling sample circulated among the laboratories, generating a reference electromagnetic field whose amplitude was a priori known (with uncertainty) but not revealed to the participants until the end of the comparison. Measurement results were provided by the participants in terms of best estimate and uncertainty. The aggregate measurement result is here compared with the a priori known value and its uncertainty. The performance of the laboratories, quantified in terms of two performance statistics selected from ISO 13528, is analyzed and discussed. The measurement uncertainty declared by the laboratories is compared with the dispersion of the measurement results. Aspects concerning the design and conduct of the comparison are also presented and discussed.

The Rice probability density function has received considerable attention for its various important technical and scientific applications. One of the more attractive techniques for extracting the distribution parameters, and possibly the most frequently applied, relies on the maximization of the likelihood function for a given set of experimentally determined samples, and many applications are documented in the literature. This paper offers a mathematical analysis which demonstrates that, subject to conditions universally verified in physical systems, an absolute maximum exists, and it is the unique point internal to the domain of existence which zeroes the gradient of the likelihood function. In all previous results, the presence of additional maxima, which are possibly larger than the one that had numerically been found, could not be excluded. We can incidentally state that this paper demonstrates that all previous results based on numerically finding a maximum indeed corresponded to absolute maxima. The mathematical derivations offered here are also suggestive of actions capable of improving the insight into the maximum-likelihood technique and its numerical implementation.

In this two-parts paper, methods for the quantification of uncertainty in measurement and computational modeling are reviewed, with an emphasis on applications in electromagnetic compatibility (EMC). The current status of international standards relating to measurement uncertainty in EMC is provided (in part I), as well as a review of selected alternative methods and recent developments in the domain of computational modeling and empirical uncertainty quantification (in part II).

In this paper, the results of two proficiency tests of radiated emission measurements are reported. In doing this, several considerations are made concerning the design and realization of the traveling samples, the determination of the reference values and the selection of the statistics through which the performance of the participants to the proficiency test is assessed. Emphasis is placed on the advantages stemming from the assignment of a reference value and its uncertainty to the traveling sample before the start of the proficiency test and based on numerical predictions carried out assuming different test environments and distances between the radiator and the receiving antenna.

In Part I of this two-part contribution on uncertainty quantification (UQ) in electromagnetic compatibility and electromagnetic interference, the current status of international standards relating to measurement uncertainty is reviewed. Here in Part II, a selection of recent developments in analytical and computational modeling of uncertainty and empirical UQ is reviewed.