Statistical measurements of fast changing electromagnetic fields
The present works aims at describing important statistical indexes such as the field uniformity, the field inhomogeneity and the statistics near the cavity walls for a special case of fast changing random electromagnetic
fields. We generate this kind of electromagnetic environment by means of a vibrating intrinsic reverberation chamber. The use of several, fast, in-house, 3-axis field sensors allows for extensive, "real-time" measurements inside such a chamber.
Simultaneous multi-probe measurements for rapid evaluation of reverberation chambers
A fast measurement procedure has been developed for the evaluation of both a 1 m × 1.3 m × 1.5 m classical mode-stirred reverberation chamber (RC) and a 1 m × 1.2 m × 1.5 m vibrating intrinsic reverberation chamber (VIRC), and the results are presented. A brief description of the measurement setup is given. Measurements were performed by using very fast and accurate 9 3D electric field probes, energized via a laser and readout via an optical link, thus not disturbing the electromagnetic field. The measurement set-up and results have been evaluated showing that by using a fast multi-probe system inside a RC, much more data can be obtained much faster. This allows faster evaluation, more accurately capturing field variations, especially for RC calibration purposes and radiated immunity assessment. Moreover, some basic parameters such as field behavior, the average (spatial) field distribution between a 9-different position in 3-axis of the field inside the chamber have also been shown.
Effect of Broad-banding Amplifiers on E-field Probe Measurements in a Reverberant Cavity
Abstract : Broad-band electric-field probes have gained wide-spread acceptance for use in reverberation chambers in recent years, primarily due to their ease of use. However, recent work with AOD has highlighted situations where E-field probes may return ambiguous results. In particular, the SR may be greatly affected by the wide-band frequency reception of an E-field probe when in the presence of multiple frequencies in a reverberant environment Monte Carlo simulations conducted to examine the effects of multiple frequencies on probe measurements in a reverberant cavity were compared with experimental data that was taken by an E-field probe that was in the presence of an amplifier exhibiting distortion in a reverberation chamber. The experimental results indicate that considerable care should be taken to ensure frequency purity in a reverberant environment when making E-field probe measurements.