We numerically investigate the interaction of nonlinear pulses in coupled transmission lines with regularly spaced Schottky varactors. The c mode and π mode are two different propagation modes that can be developed on a coupled line. Recently, we have found that both modes can support soliton-like pulses due to the presence of the Schottky varactors and proposed a method of doubling repetition rate of the incident pulse stream. Through numerical evaluations, we find that small c-mode pulses are generated by colliding two π-mode pulses traveling in the opposite directions. Utilizing this unique property, the repetition rate of incident pulse stream can be increased by the factor greater than 2.
2. Rodwell, M. J. W., S. T. Allen, R. Y. Yu, M. G. Case, U. Bhattacharya, M. Reddy, E. Carman, M. Kamegawa, Y. Konishi, J. Pusl, and R. Pullela, "Active and nonlinear wave propagation devices in ultrafast electronics and optoelectronics," Proc. IEEE, Vol. 82, 1037-1059, 1994.
3. Kintis, M., X. Lan, and F. Fong, "An MMIC pulse generator using dual nonlinear transmission lines," IEEE Microwave Wireless Compo. Lett., Vol. 17, No. 6, 454-456, 2007.
4. Yildirim, O. O., D. S. Ricketts, and D. Ham, "Reflection soliton oscillator," IEEE Trans. Microwave Theory Tech., Vol. 57, No. 10, 2344-2353, 2009.
5. Gupta, K. C., R. Garg, and I. J. Bahl, Microstrip Lines and Slotlines, Artech, 1979.
6. Narahara, K., "Coupled nonlinear transmission lines for doubling repetition rate of incident pulse streams," Progress In Electromagnetics Research Letters, Vol. 16, 69-78, 2010.
7. Ricketts, D. S., X. Li, N. Sun, K. Woo, and D. Ham, "On the self-generation of electrical soliton pulses," IEEE J. Solid-state Circuits, Vol. 42, No. 8, 1657-1668, 2007.