Cui, Yong (2007) A new measure for evaluating shielding performance of an equipment enclosure at frequencies above 1 GHz. PhD thesis, University of York.
Abstract
The measure of shielding effectiveness (SE) and the related measurement techniques
proposed by the current IEEE Standard 299 are only applicable for large screened
enclosures having dimensions more than 2 m. To propose reasonable measures to
assess the shielding performance of an equipment enclosure, together with the
relevant measurement techniques, is the subject of this thesis. This work is informing
the new developments in IEEE Standard 299.
To coincide with the practical applications of most equipment enclosures, two
measurement approaches distinguished by the location of the radiation source are
considered in this thesis, and the measurement is performed in the radiating nearfield with test frequencies above 1 GHz. The contents inside the enclosure are
stressed and involved in all the measurements.
In the first measurement approach, to measure the enclosure’s ability to prevent the
electromagnetic waves of internal contents from radiating outside to cause
interference with nearby equipments, an emission source is -placed inside the
enclosure and a receive antenna is placed outsic’j. A new measure shielding of
radiating power (SRP) is proposed here, which consists of two parameters: the
average shielding of radiating power (ASRP) and the enhancement factor E.F.g5lh.
Two measurement environments: anechoic chamber and reverberation chamber are
considered and compared. To avoid the huge measurement work in an anechoic
chamber, the reverberation chamber is proposed as an ideal test environment to
determine the ASRP, and the estimation of the enhancement factor E.F.gnh can be
given directly based on statistic analyses on both measurement and simulation results.
In the second measurement approach, to measure the enclosure’s ability to shield the
internal contents against external interference, the enclosure is placed in a small
reverberation chamber and illuminated by external electromagnetic field. Another
new measure shielding of absorption cross section (SACS) is proposed here.
However, measurement results indicate this measure has distinct advantages and
disadvantages, so it is suggested prudently. Finally the first measure is proposed and
reverberation chamber is suggested as the ideal test environment.
Metadata
Awarding institution: | University of York |
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Academic Units: | The University of York > School of Physics, Engineering and Technology (York) |
Academic unit: | Department of Electronics |
Identification Number/EthosID: | uk.bl.ethos.542805 |
Depositing User: | EThOS Import (York) |
Date Deposited: | 24 Jul 2020 11:30 |
Last Modified: | 21 Mar 2024 15:40 |
Open Archives Initiative ID (OAI ID): | oai:etheses.whiterose.ac.uk:26196 |
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