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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.

Information

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

1 European Standard EN 55011, Limits and methods of measurement of radio interference characteristics of industrial, scientific and medical (ISM) radio-frequency equipment, 1991.Google Scholar
2 Happell, George E. and Hesselberth, Wilgred M., Engineering electronics, Mc Graw-Hill Book Company, Inc. New York, 1953, p 345–384.Google Scholar
3 Van Loock, W., “EMC of cordless telephones and 900 MHz ISM sources”, EMC Conference, Zurich 1989, paper 112 R4.Google Scholar
4 Van Loock, W., “Microwaves at 896/915 MHz as a valuable ISM tool and how to avoid interference”, Australia's Electronics Convention Proc. 1991, p 501–504.Google Scholar
5 Van Loock, W., “Broadband ISM operation for the reduction of radiated emissions”, Int. Wroclaw Symposium on EMC, June 1996, paper 69/13.Google Scholar
6 Mackay B., A., Tinga, W.R. and Voss, W.A.G., “Frequency agile sources for microwave ovens”, J. Microwave power, 14 (1), 1979, p. 63–76.Google Scholar