A Vibrating Intrinsic Reverberation Chamber (VIRC) has been installed in a semi-anechoic chamber that is normally used for electromagnetic interference test in the automotive industry and its performances evaluated. This hybrid strategy permits converting a traditional semi-anechoic chamber into a reverberating environment in a few hours. Furthermore, the proposed solution makes possible the use of two different types of testing environment without searching for additional space in the testing house. The work analyzes some figure of merits that are normally used for traditional reverberation chambers like the autocorrelation of the electromagnetic field and its statistical uniformity and isotropy properties. The analysis is performed in the frequency range from 100 MHz to 6 GHz in a 26 m x 8 m x 6 m cavity. The experimental datasets are finally tested through a goodness-offit test for checking their convergence to theoretical values.

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The Vibrating Intrinsic Reverberation Chamber (VIRC) is a special resonant cavity with flexible conductive walls. It can be used to check the susceptibility of electronic equipment to external radiated electromagnetic fields. This work suggests a closed-loop calibration method to adjust the expected level of the field strength in the working volume of the cavity. The regulation of the field level is based on its average value and is particularly useful whenever the VIRC is used as temporary installation to transform a semi-anechoic chamber in a reverberation environment. In this case, a closed-loop calibration method appears to be more suitable as it permits fast regulation of the test field after new installation of the test environment.

The dwell time is an important factor when conducting a radiated immunity test and shall be compatible with the response time of the device under investigation. In mode-stirred reverberation chambers, like the vibrating intrinsic reverberation chamber, the electromagnetic field is continuously stirred by the flexible, vibrating walls of the cavity and the time duration of high-strength interferences is generally unknown. Therefore, concerns have arisen regarding the proportion of time that the electromagnetic field level spends at or above the target level during the test. This study investigates, through empirical and simulated data, the expected value of this time interval, considering a threshold level equals to the quantile-80% of the field samples distribution. This information is useful for the user of the method, when considering a modestirred reverberation environment for devices with a wellknown response time.

Reverberation environments permit creating a statistically homogenous and isotropic electromagnetic field for testing electronic devices. Vibrating intrinsic reverberation chambers are one of the possible reverberation environments where successive, independent samples of the electromagnetic field values are generated through the vibrations of the flexible walls. In this paper, we investigate the test time (the dwell time) necessary for creating dataset of independent field sample values with homogenous statistics in a 1.5 m x 1.2 m x 1.0 m vibrating cavity. In particular, we present the results of an experimental study conducted at frequencies close the lowest usable frequency. We have compared empirical to simulated datasets showing that a prediction, based only on a theoretical approach, of the minimum dwell time could lead to large errors when nonidealities in the stirring process appear.