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Spread Spectrum Microwave Power Generation for Improving Efficiency

Published online by Cambridge University Press:  10 February 2011

W. M. Van Loock
W. M. Van Loock*
Affiliation:
University of Ghent, B-9000 Ghent, Belgium, vanloock@intec.rug.ac.be
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Abstract

Microwave power for heating applications is normally generated in the designated ISM frequency bands which occupy a band of 4%. Actual microwave generators, such as are used in domestic ovens utilise only a small fraction of this bandwidth. It is being demonstrated that spreading the power uniformly over the full ISM band by controlled frequency modulation dramatically reduces all levels of potential electromagnetic interference. With such controlled modulation telecommunication channels can operate within the ISM bands without serious problems because the leakage levels are reduced by 20 to 30 dB with no additional shielding costs. One simple (though not optimum) modulating waveform is a large ripple voltage on the magnetron power supply. Frequency modulation that spreads the energy over the full ISM band also improves the overall energy efficiency in multimode heating applications.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 430: Symposium O – Microwave Processing of Materials V , 1996 , 481
Copyright
Copyright © Materials Research Society 1996

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References

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