This paper presents lumped dual-frequency impedance transformers for frequency-dependent complex loads. According to different dual-frequency allocations of a complex load in Smith chart, three types of impedance matching networks are presented respectively. Several kinds of lumped circuit blocks are used as basic element for constructing these transformers with design formula deduced. Various examples are given for describing the design procedures.~Good features such as big frequency ratio and big matching bandwidths are demonstrated. These lumped dual-frequency impedance transformers have advantage of much compacter dimensions compared to distributive solutions.
"Lumped Dual-Frequency Impedance Transformers for Frequency-Dependent Complex Loads," Progress In Electromagnetics Research,
Vol. 126, 121-138, 2012. doi:10.2528/PIER11121207
1. Anguera, J., C. Puente, and C. Borja, "Dual frequency broadband microstrip antenna with a reactive loading and stacked elements," Progress In Electromagnetics Research Letters, Vol. 10, 1-10, 2009. doi:10.2528/PIERL09040704
2. Behera, S. and K. J. Vinoy, "Microstrip square ring antenna for dual-band operation," Progress In Electromagnetics Research, Vol. 93, 41-56, 2009. doi:10.2528/PIER09021909
3. Alkanhal, M. A. S., "Dual-band bandpass-fiillters using inverted stepped-impedance resonators," Journal of Electromagnetic Waves and Applications, Vol. 23, No. 8-9, 1211-1220, 2009.
4. Fallahzadeh, S., H. Bahrami, and M. Tayarani, "A novel dual-band bandstop waveguide filter using split ring resonators," Progress In Electromagnetics Research Letters, Vol. 12, 133-139, 2009. doi:10.2528/PIERL09103103
5. Lin, W.-J., C.-S. Chang, J.-Y. Li, D.-B. Lin, L.-S. Chen, and M.-P. Houng, "A new approach of dual-band filters by stepped impedance simplified cascaded quadruplet resonators with slot coupling ," Progress In Electromagnetics Research Letters, Vol. 9, 19-28, 2009. doi:10.2528/PIERL09042801
6. Velazquez-Ahumada, M. D. C., J. Martel-Villagr, F. Medina, and F. Mesa, "Application of stub loaded folded stepped impedance resonators to dual band filters," Progress In Electromagnetics Research, Vol. 102, 107-124, 2010. doi:10.2528/PIER10011406
7. He, J., B.-Z. Wang, and K.-H. Zhang, "Arbitrary dual-band coupler using accurate model of composite right/left handed transmission line," Journal of Electromagnetic Waves and Applications, Vol. 22, No. 8-9, 1267-1272, 2008. doi:10.1163/156939308784158760
8. De Castro-Galan, D., L. E. Garcia Munoz, D. Segovia-Vargas, and V. Gonzalez-Posadas, "Diversity monopulse antenna based on a dual-frequency and dual mode CRLH rat-race coupler," Progress In Electromagnetics Research B, Vol. 14, 87-106, 2009. doi:10.2528/PIERB09030603
9. Lin, Z. and Q.-X. Chu, "A novel approach to the design of dual-band power divider with variable power dividing ratio based on coupled-lines," Progress In Electromagnetics Research, Vol. 103, 271-284, 2010. doi:10.2528/PIER10012202
10. Chaudhary, G., Y. Jeong, K. Kim, and D. Ahn, "Design of dual-band bandpass filters with controllable bandwidths using new mapping function," Progress In Electromagnetics Research, Vol. 124, 17-34, 2012. doi:10.2528/PIER11111407
11. Chen, W.-Y., M.-H. Weng, S.-J. Chang, H. Kuan, and Y.-H. Su, "A new tri-band bandpass filter for GSM, WiMAX and ultra-wideband responses by using asymmetric stepped impedance resonators," Progress In Electromagnetics Research, Vol. 124, 365-381, 2012. doi:10.2528/PIER11122010
12. Liu, J.-C., K.-D. Yeh, C.-C. Yen, C.-Y. Liu, B.-H. Zeng, and C.-C. Chen, "Miniaturized dual-mode resonators with improved double square loop and inter-digital couple for WLAN dual-bands," Progress In Electromagnetics Research C, Vol. 24, 123-136, 2011. doi:10.2528/PIERC11081006
13. Shao, J., H. Zhang, C. Chen, S. Tan, and K. J. Chen, "A compact dual-band coupled-line balun with tapped open-ended stubs," Progress In Electromagnetics Research C, Vol. 22, 109-122, 2011. doi:10.2528/PIERC11050205
14. Wang, C.-J., Y.-J. Lee, and K.-C. Lee, "A dual-band CPW-FED l-slot antenna with both linear and circular polarizations," Progress In Electromagnetics Research C, Vol. 21, 229-241, 2011.
15. Li, X., Y.-J. Yang, L. Yang, S.-X. Gong, X. Tao, Y. Gao, K. Ma, and X.-L. Liu, "A novel design of dual-band unequal wilkinson power divider," Progress In Electromagnetics Research C, Vol. 12, 93-100, 2010. doi:10.2528/PIERC10010705
16. Li, W.-M., Y.-C. Jiao, L. Zhou, and T. Ni, "Compact dual-band circuilarly polarized monopole antenna," Journal of Electromagnetic Waves and Applications, Vol. 25, No. 14-15, 2130-2137, 2011. doi:10.1163/156939311798072018
17. Monzon, C., "A small dual-frequency transformer in two sections," IEEE Transactions on Microwave Theory and Techniques, Vol. 51, No. 4, 1157-1161, 2003. doi:10.1109/TMTT.2003.809675
18. Park, M. J. and B. Lee, "Dual band design of single stub impedance matching networks with application to dual band stubbed T junctions," Microw. Opt. Technol. Lett., Vol. 52, No. 6, 1359-1362, 2010. doi:10.1002/mop.25201
19. Wu, Y., Y. Liu, and S. Li, "A dual-frequency transformer for complex impedances with two unequal sections," IEEE Microw. Wirel. Compon. Lett., Vol. 19, No. 2, 77-79, 2009. doi:10.1109/LMWC.2009.2034034
20. Liu, X., Y. Liu, S. Li, F. Wu, and Y. Wu, "A three-section dual-band transformer for frequencydependent complex load impedance," IEEE Microw. Wirel. Compon. Lett., Vol. 19, No. 10, 611-613, 2009. doi:10.1109/LMWC.2009.2029732
21. Chuang, M. L., "Dual-band impedance transformer using two-section shunt stubs," IEEE Transactions on Microwave Theory and Techniques, Vol. 58, No. 5, 1257-1263, 2010. doi:10.1109/TMTT.2010.2045560
22. Nikravan, M. A. and Z. Atlasbaf, "T-section dual-band impedance transformer for frequency-dependent complex impedance loads," Electronics Letters, Vol. 47, No. 9, 551-553, Apr. 2011. doi:10.1049/el.2010.7452
23. Wu, Y., Y. Liu, S. Li, C. Yu, and X. Liu, "A generalized dual-frequency transformer for two arbitrary complex frequency-dependent impedances," IEEE Microw. Wirel. Compon. Lett., Vol. 19, No. 12, 792-794, 2009. doi:10.1109/LMWC.2009.2034034
24. Fukuda, A., H. Okazaki, and S. Narahashi, "Novel multi-band matching scheme for highly efficient power amplifier," Proceedings of the 39th European Microwave Conference, 1086-1089, Rome, Italy, Sep. 2009.
25. Nallam, N. and S. Chatterjee, "Design of concurrent multi-band matching networks," IEEE International Symposium on Circuits and Systems, 201-204, Rio de Janeiro, Brazil, May 2011.