A computationally efficient, integrated and dynamic model has been developed for the design of a planar Slow Wave Structure (SWS) and beam-wave interaction analysis of a planar THz Traveling Wave Tube (TWT) with sheet beam. A Staggered Double Vane-Slow Wave Structure (SDV-SWS) is used for its numerous advantages over other types of SWSs. The integrated model determines RF performance of a planar TWT directly from the given beam voltage and center frequency by performing three different tasks, (i) determining geometrical parameters of a SDV-SWS of maximum possible bandwidth and high interaction impedance, (ii) determining RF circuit parameters of a SDV-SWS, and (iii) performing beam-wave interaction analysis of a planar TWT. The model was developed by adopting numerically computing environment, MATLAB. Also, highly accurate numerical techniques with double precision were used, e.g. Sixth Order Runge Kutta Method was used for electron beam dynamic. The model was used to design and simulate a 0.22 THz Sheet Beam TWT of 100W output power. The energy balance factor was achieved within ±0.001% over a very wide dynamic range from even 100 dB below saturation to more than 10 dB above saturation. The power growth of the forward wave was achieved with exactly 1 dB/dB. The program is fast enough for interactive use on a standard computer with a basic configuration. The model has been compared with the published works using 3D electromagnetic field simulator for demonstrating its accuracy.
2. Sirtori, C., "Applied physics: Bridge for the terahertz gap," Nature, Vol. 417, No. 9, 132-133, May 2002.
3. Mineo, M. and C. Paoloni, "Double corrugated rectangular waveguide slow-wave structure for terahertz vacuum devices," IEEE Transactions on Electron Devices, Vol. 57, No. 11, 3169-3175, 2010.
4. Goplen, B., L. Ludeking, D. Smithe, and G.Warren, "User-configurableMAGIC for electromagnetic PIC calculations," Comput. Phys. Commun., Vol. 87, No. 1, 54-86, May 1995.
5. Srivastava, V. and R. G. Carter, "A fast large-signal model for coupled-cavity TWT," IEEE Transactions on Electron Devices, Vol. 35, No. 11, 2068-2076, Nov. 1988.
6. Srivastava, V. and D. Sharma, "Design of a broadband planar RF structure for a 0.22 THz traveling wave tube," Universal Journal of Electrical and Electronics Engineering (USA), Vol. 5, No. 1, 9-19, 2017.
7. Xie, W., Z. Cheng, J. Luo, and Q. Liu, "Theory and simulation of arbitrarily shaped grooved staggered double grating array waveguide," IEEE Transactions on Electron Device, Vol. 61, No. 6, 1707-1714, Jun. 2014.
8. Lei, X., Y. Wei, Y. Wang, Q. Zhou, G. Wu, C. Ding, Q. Li, L. Zhang, X. Jiang, Y. Gong, and W. Wang, "Full-wave analysis of the high-frequency characteristics of the sine waveguide slow-wave structure," AIP Advances, Vol. 7, 085111, 2017.
9. Srivastava, V., "Nonlinear analysis of beam-wave interaction in a planar THz travelling-wave tube amplifier," Journal of Electromagnetic Waves and Applications, Vol. 32, No. 2, 190-203, 2017.
10. Fu, C., Y. Wei, B. Zhao, Y. Yang, and Y. Ju, "One-dimensional nonlinear theory for rectangular helix traveling-wave tube," AIP Physics of Plasma, Vol. 23, 083123, 2016.
11. Dormand, J. R. and P. J. Prince, "A family of embedded Runge-Kutta formulae," Journal of Computational and Applied Mathematics, Vol. 6, No. 1, 19-26, Mar. 1980.
12. Tsitouras, C. and T. E. Simos, "Optimized Runge-Kutta pairs for problems with oscillating solutions," Journal of Computational and Applied Mathematics, Vol. 147, No. 2, 397-402, Oct. 2002.
13. Yin, H., J. Xu, L. Yue, Y. Gong, and Y. Wei, "A method to calculate output power for sheetbeam traveling wave tube," IEEE Transactions on Electron Devices, Vol. 59, No. 12, 3630-3634, Dec. 2012.
14. Xie, W., Z.-C. Wang, and J. Luo, "A 3-D large signal model for sheet beam traveling wave tubes," IEEE Transactions on Electron Devices, Vol. 62, No. 3, 1010-1016, Mar. 2015.