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15 - Magnetrons

Published online by Cambridge University Press:  27 April 2018

Richard G. Carter
Richard G. Carter
Affiliation:
Lancaster University
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Summary

In a travelling-wave tube amplifier (TWT) a linear electron beam interacts with the longitudinal r.f. electric field of a slow-wave structure. Approximate synchronism between the electrons and the wave on the structure is maintained over a wide band of frequencies in low power tubes using helix slow-wave structures. High power tubes using coupled-cavity structures have narrower bandwidths. The structure is divided into two or more sections by severs to prevent feedback oscillations in high gain tubes. The initial velocity of the electrons is slightly greater than the phase velocity of the wave on the structure. The mean velocity of the electrons decreases as some of their kinetic energy is transferred to the wave and the beam becomes bunched. The power output saturates when the velocity of the bunches is equal to the velocity of the wave. The saturated output power can be increased by tapering the output end structure to reduce its phase velocity. Small- and large-signal modelling gives understanding of the principles of operation of a TWT including the factors affecting efficiency. The design of TWTs for octave bandwidth, multi-octave bandwidth, high efficiency, millimetre wave, and high power operation is considered in detail. Hybrid tubes are considered briefly.
Type
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Information
Microwave and RF Vacuum Electronic Power Sources , pp. 565 - 628
Publisher: Cambridge University Press
Print publication year: 2018

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References

Okress, E., Ed., Crossed-Field Microwave Devices. New York: Academic Press, 1961.Google Scholar
Gilmour, A. S., Jr., Klystrons, Traveling Wave Tubes, Magnetrons, Crossed-Field Amplifiers and Gyrotrons. Norwood, MA: Artech House, 2011.Google Scholar
Sivan, L., Microwave Tube Transmitters. Kluwer Academic Publishers, 1994.Google Scholar
Brown, W. C., ‘The microwave magnetron and its derivatives’, IEEE Transactions on Electron Devices, vol. 31, pp. 1595–1605, 1984.CrossRefGoogle Scholar
Faillon, G. et al., ‘Microwave tubes’, in Eichmeier, J. A. and Thumm, M. K., eds, Vacuum Electronics: Components and Devices. Berlin: Springer-Verlag, pp. 1–84, 2008.Google Scholar
Gold, S. H. and Nusinovich, G. S., ‘Review of high-power microwave source research’, Review of Scientific Instruments, vol. 68, p. 3945–3974, 1997.CrossRefGoogle Scholar
Benford, J. et al., High Power Microwaves. CRC Press, 2015.CrossRefGoogle Scholar
Hull, J. F., ‘Inverted Magnetron’, Proceedings of the IRE, vol. 40, pp. 1038–1041, 1952.CrossRefGoogle Scholar
Slater, J. C., Microwave Electronics. New York: D. van Nostrand, 1950.Google Scholar
Skowron, J. F., ‘The continuous-cathode (emitting-sole) crossed-field amplifier’, Proceedings of the IEEE, vol. 61, pp. 330–356, 1973.CrossRefGoogle Scholar
Smith, W. A., ‘A wave treatment of the continuous cathode crossed-field amplifier’, IRE Transactions on Electron Devices, vol. 9, pp. 379–387, 1962.CrossRefGoogle Scholar
Hutter, R. G. E., Beam and Wave Electronics in Microwave Tubes. Princeton, NJ: D. van Nostrand, 1960.Google Scholar
Vaughan, J. R. M., ‘A model for calculation of magnetron performance’, IEEE Transactions on Electron Devices, vol. 20, pp. 818–826, 1973.CrossRefGoogle Scholar
Collins, G. B., Microwave Magnetrons. New York: McGraw-Hill, 1948.Google Scholar
Kroll, N., ‘The unstrapped resonant system’, in Collins, G. B., ed., Microwave Magnetrons. New York: McGraw-Hill, pp. 49–82, 1948.Google Scholar
Millman, S. and Smith, W. V., ‘The resonant system’, in Collins, G. B., ed., Microwave Magnetrons. New York: McGraw-Hill, pp. 460–502, 1948.Google Scholar
Carter, R. G., Electromagnetism for Electronic Engineers. Fredriksberg, Denmark: Ventus Publishing, 2010.Google Scholar
Gilgenbach, R. M. et al., ‘Cathode priming of magnetrons for rapid startup and mode-locking’, in The Joint 30th International Conference on Infrared and Millimeter Waves and 13th International Conference on Terahertz Electronics, vol. 2, pp. 535–536, 2005.Google Scholar
Neculaes, V. B. et al., ‘Magnetic perturbation effects on noise and startup in DC-operating oven magnetrons’, IEEE Transactions on Electron Devices, vol. 52, pp. 864–871, 2005.CrossRefGoogle Scholar
Neculaes, V. B. et al., ‘Magnetic priming effects on noise, startup, and mode competition in magnetrons’, IEEE Transactions on Plasma Science, vol. 33, pp. 94–102, 2005.CrossRefGoogle Scholar
Kim, J. I. et al., ‘Reduction of noise in strapped magnetron by electric priming using anode shape modification’, Applied Physics Letters, vol. 88, p. 221501, 2006.CrossRefGoogle Scholar
Smith, W. V., ‘Mechanical tuning’, in G. B. Collins, ed., Microwave Magnetrons. New York: McGraw-Hill, pp. 561–591, 1948.Google Scholar
Bernstein, M. J. and Kroll, N. M., ‘Mechanically tuned rising-sun magnetrons’, in E. Okress, ed., Crossed-Field Microwave Devices, vol. 2. New York: Academic Press, pp. 149–153, 1961.CrossRefGoogle Scholar
Nelson, R. B., ‘Methods of tuning multiple-cavity magnetrons’, Proceedings of the IRE, vol. 36, pp. 53–56, 1948.CrossRefGoogle Scholar
Pickering, A. et al., ‘Electronically tuned pulse magnetron’, in IEEE International Electron Devices Meeting, pp. 145–148, 1975.Google Scholar
Yu, S. P. and Hess, P. N., ‘Slow-wave structures for M-type devices’, IRE Transactions on Electron Devices, vol. 9, pp. 51–57, 1962.CrossRefGoogle Scholar
Hull, J. F., ‘Crossed field electron interaction in space charge limited beams’, Doctor of Electrical Engineering, Polytechnic Institute of Brooklyn, New York, 1958.Google Scholar
Feinstein, J. and Collier, R. J., ‘The circular electric mode magnetron’, in Okress, E., ed., Crossed-Field Microwave Devices, vol. 2. New York: Academic Press, pp. 123–134, 1961.CrossRefGoogle Scholar
Bamford, A. J. et al., ‘A 1-MW L-band coaxial magnetron with separate cavity’, IEEE Transactions on Electron Devices, vol. 14, pp. 844–851, 1967.CrossRefGoogle Scholar
Ruden, T. E., ‘Design and performance of a one megawatt, 3.1–3.5 GHz coaxial magnetron’, in 9th European Microwave Conference, pp. 731–735, 1979.Google Scholar
Pickering, A. H., ‘Further developments of long anode magnetrons’, in Okress, E., ed., Crossed Field Microwave Devices, vol. 2. New York: Academic Press, pp. 275–290, 1961.CrossRefGoogle Scholar
Boot, H. A. H., ‘Long anode magnetrons’, in Okress, E., ed., Crossed Field Microwave Devices, vol. 2. New York: Academic Press, pp. 261–274, 1961.CrossRefGoogle Scholar
Boot, H. A. H. et al., ‘A new design of high-power S-band magnetron’, Proceedings of the IEE – Part B: Radio and Electronic Engineering, vol. 105, pp. 419–425, 1958.Google Scholar
Feng, J.-J. et al., ‘Simulation of a long anode magnetron resonant system using MAFIA’, in International Conference on Microwave and Millimeter Wave Technology, pp. 748–751, 1998.CrossRefGoogle Scholar
Smith, A. G., ‘Typical magnetrons’, in Collins, G. B., ed., Microwave Magnetrons. New York: McGraw-Hill, pp. 739–796, 1948.Google Scholar
Schumacher, C. R., ‘Frequency pushing’, in Okress, E., ed., Crossed-Field Microwave Devices, vol. 2. New York: Academic Press, pp. 401–422, 1961.Google Scholar
Welch, H. W., ‘Prediction of traveling wave magnetron frequency characteristics: frequency pushing and voltage tuning’, Proceedings of the IRE, vol. 41, pp. 1631–1653, 1953.CrossRefGoogle Scholar
Pritchard, W. L., ‘Long-line effect and pulsed magnetrons’, IRE Transactions on Microwave Theory and Techniques, vol. 4, pp. 97–110, 1956.CrossRefGoogle Scholar
Yokoyama, R. and Yamada, A., ‘Development status of magnetrons for microwave ovens’, in Microwave Power Symposium, pp. 132–135, 1996.Google Scholar
Osepchuk, J. M., ‘The cooker magnetron as a standard in crossed-field device research’, in 1st Int. Workshop on Crossed-Field Devices, University of Michigan, USA, pp. 159–177, 1995.Google Scholar
Schumacher, C. R., ‘Spectrum shape’, in Okress, E., ed., Crossed-Field Microwave Devices, vol. 2. New York: Academic Press, pp. 457–471, 1961.CrossRefGoogle Scholar
Carter, R. G. et al., ‘Magnetron frequency twinning’, IEEE Transactions on Plasma Science, vol. 28, pp. 905–909, June 2000.Google Scholar
‘Preamble: Magnetrons’, Chelmsford, UK: EEV Ltd., 1974.Google Scholar
Varian, ‘Technical Manual: Installation, Operation, Maintenance, Care and Handling Instructions, General: Microwave Tubes, Magnetron Tubes, Electron Tubes’, 1 October 1979.Google Scholar
Adler, R., ‘A study of locking phenomena in oscillators’, Proceedings of the IRE, vol. 34, pp. 351–357, 1946.CrossRefGoogle Scholar
Thal, H. L. and Lock, R. G., ‘Locking of magnetrons by an injected RF signal’, IEEE Transactions on Microwave Theory and Techniques, vol. 13, pp. 836–846, 1965.CrossRefGoogle Scholar
Tahir, I. et al., ‘Noise performance of frequency- and phase-locked CW magnetrons operated as current-controlled oscillators’, IEEE Transactions on Electron Devices, vol. 52, pp. 2096–2103, September 2005.CrossRefGoogle Scholar
Tahir, I. et al., ‘Frequency and phase modulation performance of an injection-locked CW magnetron’, IEEE Transactions on Electron Devices, vol. 53, pp. 1721–1729, July 2006.CrossRefGoogle Scholar
Brown, W. C., ‘The sophisticated properties of the microwave oven magnetron’, in IEEE MTT- S International Microwave Symposium Digest, vol. 3, pp. 871–874, 1989.CrossRefGoogle Scholar
David, E. E., Jr., ‘Phasing by RF signals’, in Okress, E., ed., Crossed-Field Microwave Devices, vol. 2. New York: Academic Press, pp. 375–399, 1961.CrossRefGoogle Scholar
Kim, H. and Choi, J., ‘Characterization of a 16-vane strapped magnetron oscillator by three-dimensional particle-in-cell code simulations’, Current Applied Physics, vol. 6, pp. 66–70, 2006.CrossRefGoogle Scholar
Andreev, A. D. and Hendricks, K. J., ‘ICEPIC simulation of a strapped nonrelativistic high-power CW UHF magnetron with a solid cathode operating in the space-charge limited regime’, IEEE Transactions on Plasma Science, vol. 40, pp. 1551–1562, 2012.CrossRefGoogle Scholar
Alfadhl, Y. et al., ‘Advanced computer modelling of magnetrons’, in 2010 International Conference on the Origins and Evolution of the Cavity Magnetron (CAVMAG), pp. 67–70, 2010.CrossRefGoogle Scholar
Dombrowski, G. E., ‘Simulation of magnetrons and crossed-field amplifiers’, IEEE Transactions on Electron Devices, vol. 35, pp. 2060–2067, 1988.CrossRefGoogle Scholar
Dombrowski, G. E., ‘Computer simulation study of primary and secondary anode loading in magnetrons’, IEEE Transactions on Electron Devices, vol. 38, pp. 2234–2238, 1991.CrossRefGoogle Scholar
McDowell, H. L., ‘Magnetron simulations using a moving wavelength computer code’, IEEE Transactions on Plasma Science, vol. 26, pp. 733–754, 1998.CrossRefGoogle Scholar
McDowell, H. L., ‘Magnetron simulations using a multiple wavelength computer code’, IEEE Transactions on Plasma Science, vol. 32, pp. 1160–1170, 2004.CrossRefGoogle Scholar
Welch, H. W. and Dow, W. G., ‘Analysis of synchronous conditions in the cylindrical magnetron space charge’, Journal of Applied Physics, vol. 22, pp. 433–438, 1951.CrossRefGoogle Scholar
Hull, J. F., ‘Crossed-field electron interaction of the distributed-emission space-charge-limited type’, IRE Transactions on Electron Devices, vol. 8, pp. 309–323, 1961.CrossRefGoogle Scholar
Riyopoulos, S., ‘Magnetron theory’, Physics of Plasmas, vol. 3, pp. 1137–1161, 1996.CrossRefGoogle Scholar
Riyopoulos, S., ‘New improved formulas for magnetron characteristic curves’, IEEE Transactions on Plasma Science, vol. 26, pp. 755–766, 1998.CrossRefGoogle Scholar
Zhang, E.-Q., ‘On the magnetron cathode’, IEEE Transactions on Electron Devices, vol. 33, pp. 1383–1384, 1986.CrossRefGoogle Scholar
Feinstein, J., ‘Planar magnetron theory and applications’, in Okress, E., ed., Crossed-Field Microwave Devices, vol. 1. New York: Academic Press, 1961.Google Scholar
Clogston, A. M., ‘Principles of design’, in Collins, G. B., ed., Microwave Magnetrons. New York: McGraw-Hill, pp. 401–459, 1948.Google Scholar
Twisleton, J. R. G., ‘Twenty-kilowatt 890 Mc/s continuous-wave magnetron’, Proceedings of the Institution of Electrical Engineers, vol. 111, pp. 51–56, 1964.CrossRefGoogle Scholar
Shibata, C. et al., ‘High-power (500 kW) c.w. magnetron for industrial heating’, Electrical Engineering in Japan, vol. 111, pp. 94–100, 1991.CrossRefGoogle Scholar
Cripps, A. M. and Jerram, P. A., ‘X-band linear accelerator magnetrons’, in 19th European Microwave Conference, pp. 1086–1090, 1989.Google Scholar
Feaster, G. R., ‘The cathode’, in Okress, E., ed., Crossed-Field Microwave Devices, vol. 1. New York: Academic Press, pp. 113–140, 1961.CrossRefGoogle Scholar
Osepchuk, J. M., ‘Private communication’, 2016.Google Scholar

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  • Magnetrons
  • Richard G. Carter, Lancaster University
  • Book: Microwave and RF Vacuum Electronic Power Sources
  • Online publication: 27 April 2018
  • Chapter DOI: https://doi.org/10.1017/9780511979231.015
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To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.

  • Magnetrons
  • Richard G. Carter, Lancaster University
  • Book: Microwave and RF Vacuum Electronic Power Sources
  • Online publication: 27 April 2018
  • Chapter DOI: https://doi.org/10.1017/9780511979231.015
Available formats
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Save book to Google Drive

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.

  • Magnetrons
  • Richard G. Carter, Lancaster University
  • Book: Microwave and RF Vacuum Electronic Power Sources
  • Online publication: 27 April 2018
  • Chapter DOI: https://doi.org/10.1017/9780511979231.015
Available formats
×