We address the uncertainty of reverberation chamber (RC) measurements in presence of both mechanical and frequency stirring (FS). A base-case model is derived for reverberation fields affected by the measurement uncertainty due to the lack of a perfect statistical uniformity of fields in a RC. It is found that the measurement uncertainty associated with the FS depends on both the total uncorrelated samples and the local insertion loss (IL). The local IL depends on the frequency stirring bandwidth (FSB). The model allows us for obtaining separate measurement uncertainty contributions. Measurements support the achieved uncertainty model. In particular, results show that the dependence on the IL is normally rather weak also when very wide FSBs are used.

This paper enhances the new nested chambers shielding effectiveness approach proposed by Holloway. The enhanced model considers the multiple interactions between the two chambers and nonreciprocal samples. Results show that the enhancement is remarkable when the two chambers are tightly coupled and the shielding effectiveness is not marginal.

Average ACS can be measured in a reverberation chamber; however, the existing technique determines a value that includes the effects of the radiation efficiencies of the antennas used in the measurement. Correcting for these necessitates further complex measurements. Here, we present the theory of an alternative measurement methodology using two nested or contiguous reverberation chambers which is free from errors caused by the radiation efficiencies of the antennas. The new method is based on the theoretical average transmission cross sections (TCS) of circular holes in a metal plate between the two chambers. In fact, the method can be viewed as an accurate transfer calibration measurement between TCS and ACS that is independent of both the chamber and antenna characteristics. Further, since the existing method of measuring ACS includes the effects of the radiation efficiencies of the antennas, a comparison of the ACS of a reference object, measured using both the existing and new methods, also provides an alternative method of determining radiation antenna efficiency. Measurement uncertainties for both alternative measurement methods-ACS and antenna radiation efficiency-are also derived.

A new empirical model for the Doppler spectrum of the received field obtained in a reverberating chamber (RC) when the continuous mechanical stirring is employed, is proposed. The characterisation of the Doppler spectrum is 2‐fold: on the one side, it allows synthesising an electromagnetic field with desired characteristics within the chamber; on the other side, if the RC is used as a wireless emulator, any wireless propagation environments can be properly emulated within the chamber. The model is successfully tested on an extensive set of measurements accomplished at the RC of the Università degli Studi di Napoli Parthenope, formerly Istituto Universitario Navale (IUN). Results, confirm the effectiveness of the prosed method.

The measurement of the absorption cross section (ACS) is one of the applications of a reverberation chamber. In this letter, a statistical analysis of the uncertainty of ACS measurements is shown. The achieved model enhances the one already present in the literature and is done differently. Measurements show the importance of the uncertainty component connected to the position of the antennas and/or of the absorbing sample and how it is reduced so that the simple model based only on independent samples can be effectively used.

In this paper test study on low-cost civil engineering construction material is presented. In fact, in several civil constructions the strategy is to build up to first "fence" to EMI that limits interferences while using only in some limited areas high-cost ad hoc shielding material. The materials used in this study are tested at the Universita di Napoli Parthenope, formerly Istituto Universitario Navale (IUN) Reverberating Chamber (RC) according to a nested approach. Tests are made in the frequency range from 2 to 18 GHz and show that low-cost materials are able to achieve about 16 dB of shielding effectiveness (SE) in contrast to ad hoc materials that show about 50 dB in SE