Progress In Electromagnetics Research C
ISSN: 1937-8718
Home | Search | Notification | Authors | Submission | PIERS Home | EM Academy
Home > Vol. 16 > pp. 37-50


By H.-X. Yi, P.-K. Liu, and L. Xiao

Full Article PDF (207 KB)

Obtaining higher efficiency during the development of space Traveling Wave Tubes (TWTs) is always one of the most important goals for scientists. In this paper, a scheme of obtaining the maximum theoretical overall efficiency is explored by optimizing the helix pitch profile of a TWT based on the collectability of spent beam. The collectability of the spent beam was evaluated by the maximum collector efficiency, and this maximum collector efficiency was employed to calculate the maximum theoretical overall efficiency. The energy distribution of the spent beam and the output power of TWTs were calculated by the 3-D large signal Beam-Wave Interaction Simulator (BWIS) of MTSS. The detailed design of a Ku-band helix TWT is described according to three optimization goals (theoretical overall efficiency, theoretical collector efficiency and electronic efficiency). The simulation results indicate that the optimization for high interaction circuit efficiency or collector efficiency by itself is not adequate to obtain maximum overall efficiency. The maximum theoretical overall efficiency of 77% was achieved via the optimization of slow wave structure for theoretical overall efficiency.

H.-X. Yi, P.-K. Liu, and L. Xiao, "Numerical Optimization of Pitch Profile for Overall Efficiency Enhancement of a Space TWT," Progress In Electromagnetics Research C, Vol. 16, 37-50, 2010.

1. Duan, Z. Y., Y. B. Gong, Y. Y. Wei, W. X. Wang, B. I. Wu, and J. A. Kong, "Efficiency improvement of broadband helix traveling wave tubes using hybrid phase velocity tapering model," Journal of Electromagnetic Waves and Applications, Vol. 22, 1013-1023, 2008.

2. Zhu, Z. J., B. F. Jia, and D. M. Wan, "Efficiency improvement of helix traveling-wave tube," Journal of Electromagnetic Waves and Applications, Vol. 22, 1747-1756, 2008.

3. Komm, D. S., et al., "Advances in space TWT efficiencies," IEEE Trans. Electron Devices, Vol. 48, No. 1, Jan. 2001.

4. Srivastava, V. and R. G. Carter, "Design of helix slow wave structures for high efficiency TWTs," IEEE Trans. Electron Devices, Vol. 47, No. 12, Dec. 2000.

5. Wilson, J. D., "A simulated annealing algorithm for optimizing RF power efficiency in coupled-cavity traveling-wave tubes," IEEE Trans. Electron Devices, Vol. 44, No. 12, 2295-2299, 1997.

6. Duan, Z. Y., Y. B. Gong, Y. L. Mo, M. Y. Lü, Y. Y. Wei, and W. X. Wang, "Optimization design of helix pitch for efficiency to enhancement in the helix TWT," Chinese Physic Letter, Vol. 25, No. 3, 934-937, 2008.

7. Li, G. C., P. K. Liu, L. Xiao, and B. L. Hao, "Efficiency enhancement of helix traveling wave tube based on ε multi-objective evolutionary algorithm," J. Infrared Milli Terahz Waves, 2009.

8. Barker, R. J., et al., Modern Microwave and Millimeter-wave Power Electronics, 208-209, Willy-IEEE Press, Apr. 2005.

9. Abe, D. K., B. Levush, T. M. Antonsen, D. R. Whaley, and B. G. Danly, "Design of linear C-Band helix TWT for digital communications experiments using the christine suite of large-signal codes," IEEE Trans. Plasma Sci., Vol. 30, No. 3, Jun. 2002.

10. David, J. A., C. L. Kory, H. T. Tran, R. L. Ives, and D. Chernin, "Enhanced features for design of travelling wave tubes using christine-1D," IEEE Trans. Plasma Sci., Vol. 35, No. 4, Aug. 2007.

11. Ghosh, T. K. and R. G. Carter, "Optimization of multistage depressed collectors," IEEE Trans. Electron Devices, Vol. 54, No. 8, Aug. 2007.

12. Vaden, K. R., J. D. Wilson, and B. A. Bulson, "A simulated annealing algorithm for the optimization of multistage depressed collector efficiency," Proc. 3rd IEEE Int. Vac. Electron. Conf., 164-165, Apr. 23--25, 2002.

13. Xiao, L., Y.-H. Dong, X.-B. Su, and P.-K. Liu, "A multi-objective genetic algorithm for optimizing dispersion and coupling impedance in helix TWTs," The 7th IVEC 2006 & 6th IVESC, California, USA, 2006.

14. Razavi, S. M. J. and M. Khalaj-Amirhosseini, "Optimization an anechoic chamber with ray-tracing and genetic algorithms," Progress In Electromagnetics Research B, Vol. 9, 53-68, 2008.

15. Tokan, F. and F. Günes, "The multi-objective optimization of non-uniform linear phased arrays using the genetic algorithm," Progress In Electromagnetics Research B, Vol. 17, 135-151, 2009.

16. Li, B., et al., "Theory and design of microwave-tube simulator," IEEE Trans. Electron Devices, Vol. 56, No. 5, May 2009.

17. Malek, F., "The Analytical design of a folded aaveguide traveling wave tube and small signal gain analysis using Madey's theorem," Progress In Electromagnetics Research, Vol. 98, 137-162, 2009.

18. Seshadri, R., S. Ghosh, A. Bhansiwal, S. Kamath, and P. K. Jain, "A simple analysis of helical slow-wave structure loaded by dielectric embedded metal segments for wideband traveling-wave tubes," Progress In Electromagnetics Research B, Vol. 20, 303-320, 2010.

19. Deb, K. and R. B. Agrawal, "Simulated binary crossover for continuous search space," Complex Systems, Vol. 9, 115-148, 1995.

20. Manikas, T. W. and J. T. Cain, Genetic Algorithms vs. Simulated Annealing: A Comparison of Approaches for Solving the Circuit Partitioning Problem, University of Pittsburgh, Department of Electrical Engineering, May 1996.

21. Mann, J. W. and G. D. Smith, "A comparison of heuristics for telecommunications traffic routing," Modern Heuristic Search Methods, John Wiley & Sons, 1996.

© Copyright 2010 EMW Publishing. All Rights Reserved