This paper presents 2-way Power Divider (PD) for Ultra-Wideband (UWB) applications. The proposed power divider is realized using two cascaded sections of Wilkinson Power Divider (WPD) of equal characteristic impedances and unequal electrical lengths with inserted open stub to improve matching, isolation and to broaden the bandwidth. It is proved analytically using the ``Even Odd Mode'' analysis method and the ABCD matrix to obtain exact closed-form design equations. A detailed design methodology is introduced to facilitate the implementation without needing CAD optimization. To verify the proposed design methodology, a 2-way power divider is designed, fabricated on a Rogers RT/Duroid 5880 substrate and compared to other published 2-way microstrip power dividers. Measured data show good agreement with Electromagnetic (EM)-Circuit Co-Simulation, which proves the design equations and methodology. The proposed planar 2-way PD achieves an isolation ≥ 13.5 dB, input return loss ≥10 dB, output return loss ≥14.5 dB and exceeded insertion loss ≤ 0.9 dB (over the -3 dB splitting ratio) through the whole UWB range from 3.1 GHz to 10.6 GHz. Furthermore, it has a compact area of 22 mm × 15 mm, which provides 50% enhancement over similar microstrip PD circuits while achieving better isolation and matching.
2. Cohn, S. B., "A class of broadband three-port TEM-mode hybrids," IEEE Transactions on Microwave Theory and Techniques, Vol. 16, No. 2, 110-116, Feb. 1968.
3. El-Tager, A. M. E., A. M. A. H. El-Akhdar, and H. M. S. El-Henawy, "Analysis of coupled microstrip lines for quad-band equal power dividers/combiners," Progress In Electromagnetics Research B, Vol. 41, 187-211, 2012.
4. Kim, T., B. Lee, and M.-J. Park, "Dual-band unequal Wilkinson power divider with reduced length," Microwave and Optical Technology Letters, Vol. 52, No. 5, 1187-1190, May 2010.
5. Chi, P. and K. Ho, "Design of dual-band coupler with arbitrary power division ratios and phase differences," IEEE Transactions on Microwave Theory and Techniques, Vol. 62, No. 12, 2965-2974, Oct. 2014.
6. Kasim, F. R. H., M. A. S. Alkanhal, and A.-F. A. Sheta, "UWB Wilkinson power divider using tapered transmission lines," PIERS Proceedings, 882-884, Moscow, Russia, Aug. 19–23, 2012.
7. Mencia-Oliva, B., A. M. Pelaez-Perez, P. Almorox-Gonzalez, and J. I. Alonso, "New technique for the design of ultra-broadband power dividers based on tapered lines," 2009 IEEE MTT-S International Microwave Symposium Digest, 493-496, Boston, MA, Jun. 2009.
8. Chiang, C. T. and B.-K. Chung, "Ultra wideband power divider using tapered line," Progress In Electromagnetics Research, Vol. 106, 61-73, 2010.
9. Chang, L., C. Liao, L.-L. Chen, W. Lin, X. Zheng, and Y.-L. Wu, "Design of an ultrawideband power divider via the Coarse-Grained parallel Micro-Genetic algorithm," Progress In Electromagnetics Research, Vol. 124, 425-440, 2012.
10. Ahmed, O. and A. R. Sebak, "A modified Wilkinson power divider/combiner for ultrawideband communications," 2009 IEEE Antennas and Propagation Society International Symposium, 1-4, Charleston, SC, Jun. 2009.
11. Zhou, B., H. Wang, and W.-X. Sheng, "A modified UWB Wilkinson power divider using delta stub," Progress In Electromagnetics Research Letters, Vol. 19, 49-55, 2010.
12. Wei, F., X. W. Shi, P. Y. Qin, and Y. J. Guo, "Compact UWB power divider with unequal distribution ratio," 2014 International Workshop on Antenna Technology: Small Antennas, Novel EM Structures and Materials, and Applications (iWAT), 297-299, Sydney, NSW, Mar. 2014.
13. Liu, W.-Q., F. Wei, C.-H. Pang, and X.-W. Shi, "Design of a compact ultra-wideband power divider," 2012 International Conference on Microwave and Millimeter Wave Technology (ICMMT), Vol. 2, 1-3, Shenzhen, May 2012.
14. Abbosh, A., "Design of ultra-wideband three-way arbitrary power dividers," IEEE Transactions on Microwave Theory and Techniques, Vol. 56, No. 1, 194-201, Jan. 2008.
15. Guo, L., A. Abbosh, and H. Zhu, "Ultra-wideband in-phase power divider using stepped-impedance three-line coupled structure and microstrip-to-slotline transitions," Electronics Letters, Vol. 50, No. 5, 383-384, Feb. 2014.
16. Song, K., Y. Zhu, Q.Duan, M. Fan, and Y. Fan, "Extremely compact ultra-wideband power divider using hybrid slotline/microstrip-line transition," Electronics Letters, Vol. 51, No. 24, 2014-2015, Nov. 2015.
17. Oraizi, H. and A.-R. Sharifi, "Design and optimization of broadband asymmetrical multisection Wilkinson power divider," IEEE Trans. Microwave Theory and Techniques, Vol. 54, No. 5, 2220-2231, May 2006.
18. Shamaileh, K. A., M. Almalkawi, V. K. Devabhaktuni1, N. I. Dib, B. Henin, and A. Abbosh, "Nonuniform transmission line ultra-wideband Wilkinson power divider," Progress In Electromagnetics Research C, Vol. 44, 1-11, 2013.
19. Ahmed, O. M. H. and A. R. Sebak, "Experimental investigation of new ultra wideband in-phase and quadrature-phase power splitters," Journal of Electromagnetic Waves and Applications, Vol. 23, No. 17–18, 2261-2270, Apr. 2012.