An effective method is introduced to overcome the narrow strip width in unequal Wilkinson power divider with high dividing ratio. In the proposed method, the separated microstrip lines of the Wilkinson power divider are replaced by a uniform asymmetrical microstrip coupled lines. It is shown that in the proposed method, the width of the narrow microstrip line is significantly wider in comparison to the narrow microstrip line in the conventional Wilkinson power divider with the same specification. To design the power divider, a suitable error function is defined and then minimized which led to the final dimensions of the power divider. A sample of the designed power divider with 4:1 dividing ratio is fabricated and tested, which indicate the effectiveness of the proposed method.
2. Cohn, S. B., "A class of broadband three port TEM-mode hybrids," IEEE Trans. on Microw. Theory and Tech., Vol. 16, No. 2, 110-116, Feb. 1968.
3. Pozar, D. M., Microwave Engineering, 2nd Ed., Wiley, New York, 1998.
4. Collin, R. E., Foundations for Microwave Enginnering, 2nd Ed., McGraw Hill, 1992.
5. Lim, J.-S., S.-W. Lee, C.-S. Kim, J.-S. Park, D. Ahn, and S. Nam, "A 4 : 1 unequal Wilkinson power divider," IEEE Microw. Wireless Compon. Lett., Vol. 11, No. 3, 124-126, Mar. 2001.
6. Lim, J.-S., G.-Y. Lee, Y.-C. Jeong, D. Ahn, and K.-S. Choi, "A 1 : 6 unequal Wilkinson power divider," 36th European Microwave Conference Proceedings, 200-203, Manchester, Sep. 2006.
7. Zhang, Z., Y.-C. Jiao, S. Tu, S.-M. Ning, and S.-F. Cao, "A miniaturized broadband 4 : 1 unequal Wilkinson power divider," Journal of Electromagnetic Waves and Applications, Vol. 24, No. 4, 505-511, 2010.
8. Chen, J.-X. and Q. Xue, "Novel 5 : 1 unequal Wilkinson power divider using offset double-sided parallel-strip lines," IEEE Microw. Wireless Compon. Lett., Vol. 17, No. 3, 175-177, Mar. 2007.
9. Moradian, M. and H. Oraizi, "Application of grooved substrates for design of unequal Wilkinson power dividers," Electronics Letters, Vol. 44, No. 1, Jun. 2008.
10. Cheng, K. K. M. and P. W. Li, "A novel power divider design with unequal power dividing ratio and simple layout," IEEE Trans. on Microw. Theory and Tech., Vol. 57, No. 6, 1589-1594, Jun. 2009.
11. Wu, Y. , Y. Liu, S. Li, and C. Yu, "Extremely unequal Wilkinson power divider with dual transmission lines," Electronics Letters, Vol. 46, No. 1, 90-91, 2010.
12. Yang, T., J. Chen, and Q. Xue, "Novel approach to the design of unequal power divider with high dividing ratio," Microwave and Optical Technology Letters, Vol. 51, No. 5, 1240-1243, May 2009.
13. Li, J.-L. and B.-Z. Wang, "Novel design of Wilkinson power dividers with arbitrary power division ratios," IEEE Transactions on Industrial Electronics, Vol. 58, No. 6, 2541-2546, Jun. 2011.
14. Zhu, Y. Z., W. H. Zhu, X.-J. Zhang, M. Jiang, and G.-Y. Fang, "Shunt-stub Wilkinson power divider for unequal distribution ratio," IET. Microwaves, Antennas & Propagation, Vol. 4, No. 3, 334-341, 2010.
15. Ekinge, R. B., "A new method of synthesizing matched broadband TEM-mode three-ports," EEE Trans. on Microw. Theory and Tech., Vol. 19, No. 1, 81-88, 1971.
16. Wu, Y. and Y. Liu, "A unequal coupled-line Wilkinson power-divider for arbitrary terminated impedances," Progress In Electromagnetic Research, Vol. 117, 181-194, 2011.
17. Tripathi, V. K., "Asymmetric coupled transmission lines in an inhomogeneous medium," IEEE Trans. on Microw. Theory and Tech., Vol. 23, No. 9, 734-739, Sep. 1975.
18. Bazdar, B., A. R. Djordjevic, R. F. Harrington, and T. K. Sarkar, "Evaluation of quasi-static matrix parameters for multiconductor transmission lines using Galerkin's method," IEEE Trans. on Microwave Theory and Tech., Vol. 42, 1223-1228, Jul. 1994.