Arnaut, L R (2007) Time-domain measurement and analysis of mechanical step transitions in mode-tuned reverberation: characterization of the instantaneous field. IEEE Trans. Electromagn. Compat., 49 (4). pp. 772-784.

Full text not available from this repository.

Abstract

We report on time-domain measurements and statistical analysis of field transients that are caused by mechanical transitions between stationary states of an overmoded resonant cavity. These transitions and field transients are produced by the stepwise rotation of a mode tuner (reflective paddle wheel) inside a reverberation chamber excited by an uninterrupted time-harmonic source. It is shown that the cross-correlation function between so-called stir sequences enables the reconstruction of the average mechanical motion of the mode tuner. Evolutions of the probability distribution and statistics of the transmission S-parameter show correlation with tuner motion and demonstrate nonstationarity of the cavity field. The influence of the operating frequency and various motor parameters is investigated. In estimating the evolving maximum-to-average ratio, the variations in the underlying (parent) distribution are shown to be considerably more influential than variations of the number of independent samples. Semi- and fully-empirical estimates of this ratio are compared with directly measured values, and fully-empirical estimation} allows for more accurate prediction. It is shown that the measured local minimums and local maximums of this ratio can be identified with short- and long-tailed instantaneous parent distributions, respectively. The effect is physically interpreted as modal bunching-dilation. The results are relevant to EMC immunity testing in reverberation chambers.

Item Type:	Article
Keywords:	Electromagnetic transient fields, Wave propagation
Subjects:	Electromagnetics Electromagnetics > Wireless Communications
Last Modified:	02 Feb 2018 13:15
URI:	http://eprintspublications.npl.co.uk/id/eprint/4035

Actions (login required)

View Item