volume | PIER Journals

Abstract

Conjugately characteristic-impedance transmission lines (CCITLs) implemented by lossless periodic transmission-line structures have found various applications in microwave technology, and the T-chart was developed to perform the analysis and design of CCITLs effectively. Originally, the normalization factor used in defining normalized impedances of the T-chart is the geometric mean of characteristic impedances of CCITLs, which is not only one possible choice. By using other normalization factors based on characteristic impedances, different graphical representations can be obtained; i.e., T-charts for CCITLs with passive characteristic impedances are not unique, and it depends on the associated normalization factor. In this study, three more possible normalization factors related to characteristic impedances of CCITLs are investigated. It is found that all T-charts for each normalization factor are strongly dependent on the argument of characteristic impedances of CCITLs in a complicated fashion. The original T-chart based on the geometric mean of characteristic impedances is found to be the most convenient graphical representation for solving CCITL problems.

1. Torrungrueng, D. and C. Thimaporn, "A generalized ZY Smith chart for solving nonreciprocal uniform transmission-lines problems," Microwave and Optical Technology Letters, Vol. 40, No. 1, 57-61, 2004.
doi:10.1002/mop.11284

2. Torrungrueng, D. and C. Thimaporn, "Applications of the ZY T-chart for nonreciprocal stub tuner," Microwave and Optical Technology Letters, Vol. 45, No. 3, 259-262, 2005.
doi:10.1002/mop.20789

3. Torrungrueng, D. and C. Thimaporn, "Applications of the T-chart for solving exponentially tapered lossless nonuniform transmission-lines problems," Microwave and Optical Technology Letters, Vol. 45, No. 3, 402-406, 2005.
doi:10.1002/mop.20836

4. Torrungrueng, D., C. Thimaporn, and N. Chamnandechakun, "An applications of the T-chart for solving problems associated with terminated finite lossless periodic structures," Microwave and Optical Technology Letters, Vol. 47, No. 6, 594-597, 2005.
doi:10.1002/mop.21239

5. Lamultree, S. and D. Torrungrueng, "On the characteristics of conjugately characteristic impedance transmission lines with active characteristic impedance," Proceedings of the 2006 Asia-Pacific Microwave Conference, Vol. 1, 225-228, Yokohama, Japan, December 2006.

6. Torrungrueng, D., P. Y. Chou, and M. Krairiksh, "An extended ZY T-chart for conjugately characteristic impedance transmission lines with active characteristic impedances," Microwave and Optical Technology Letters, Vol. 49, No. 8, 1961-1964, 2007.
doi:10.1002/mop.22626

7. Torrungrueng, D. and S. Lamultree, "Equivalent graphical solutions of terminated conjugately characteristic-impedance transmission lines with non-negative and corresponding negative characteristic resistance," Progress In Electromagnetics Research, PIER 92, 137-151, 2009.

8. Wu, Y. and Y. Liu, "Standard Smith chart approach to solve exponential tapered nonuniform transmission line problems," Journal of Electromagnetic Waves and Applications, Vol. 22, No. 11-12, 1639-1646, 2008.
doi:10.1163/156939308786389997

9. Torrungrueng, D., S. Lamultree, C. Phongcharoenpanich, and M. Krairiksh, "In-depth analysis of reciprocal periodic structures of transmission lines," IET Microwaves, Antennas and Propagation, Vol. 3, 591-600, 2009.
doi:10.1049/iet-map.2008.0205

10. Zhu, Y. and R. Lee, "Tvfem analysis of periodic structures for radiation and scattering," Progress In Electromagnetic Research, PIER 25, 1-22, 2000.

11. Khalaj-Amirhosseini, M., "Analysis of periodic and aperiodic coupled nonuniform transmission lines using the fourier series expansion," Progress In Electromagnetics Research, PIER 65, 15-26, 2006.

12. Lu, W. and T.-J. Cui, "Efficient method for full-wave analysis of large-scale finite-sized periodic structures," Journal of Electromagnetic Waves and Application, Vol. 21, No. 14, 2157-2168, 2007.
doi:10.1163/156939307783152812

13. Du, P., B.-Z. Wang, H. Li, and G. Zheng, "Scattering analysis of large-scale periodic structures using the sub-entire domain basis function method and characteristic function method," Journal of Electromagnetic Waves and Application, Vol. 21, No. 14, 2085-2094, 2007.
doi:10.1163/156939307783152957

14. Fardis, M. and R. Khosravi, "Analysis of periodically loaded suspended substrate structures in millimeter wave," Progress In Electromagnetics Research B, Vol. 3, 143-156, 2008.
doi:10.2528/PIERB07120901

15. Lu, W. B., Q. Y. Zhao, and T.-J. Cui, "Sub-entire-domain basis function method for irrectangular periodic structures," Progress In Electromagnetics Research B, Vol. 5, 91-105, 2008.
doi:10.2528/PIERB08020401

Dr. Kanokwan Vudhivorn

Dr. Danai Torrungrueng

Dr. Chananya Thimaporn