volume | PIER Journals

Abstract

The design of a compact stubbed microstrip balun with very wide range higher order harmonic suppression, is presented based on multiple open stub units, for which advantages are twofold, compared to single and double open-stub based designs. First, the high degree of size and harmonic reduction is achieved within the realizable impedance values. Second, the achieved bandwidths are fairly large (close to those of conventional balun) for a given set of electrical lengths. Unlike other methods, here, predetermined bandwidth analysis is provided for various levels of size and harmonic reduction. A prototype balun, having 75% size reduction and simultaneous wide higher order harmonic suppression extended up to 12f₀, while maintaining good input matching, amplitude and phase balance bandwidths, is fabricated for validation.

1. Sturdivant, R., "Balun designs for wireless, mixers, amplifiers and antennas," Applied Microwave & Wireless, Vol. 5, No. 3, 34-44, 1993.

2. Lin, C. H., C. H. Wu, G. T. Zhou, and T. G. Ma, "General compensation method for a Marchand balun with an arbitrary connecting segment between the balance ports," IEEE Transactions on Microwave Theory and Techniques, Vol. 61, No. 8, 2821-2830, 2013.
doi:10.1109/TMTT.2013.2268057

3. Bemani, M., S. Nikmehr, and H. Takfallah, "Dual-band microstrip-to-coplanar stripline Wilkinson balun using composite right- and left-handed transmission lines and its application in feeding dual-band bow-tie antenna," IET Microwaves, Antennas & Propagation, Vol. 8, No. 7, 532-540, 2014.
doi:10.1049/iet-map.2013.0532

4. Zhang, H., Y. Peng, and H. Xin, "A tapped stepped-impedance balun with dual-band operations," IEEE Antennas and Wireless Propagation Letters, Vol. 7, 119-122, 2008.
doi:10.1109/LAWP.2008.921315

5. Barik, R. K., K. V. P. Kumar, and S. S. Karthikeyan, "Design of a dual-band microstrip branchline balun using T-shaped coupled lines," Wiley Microwave and Optical Technology Letters, Vol. 59, No. 5, May 2017.

6. Li, J. L. and S. W. Qu, "Miniaturized branch-line balun with bandwidth enhancement," Electronics Letters, Vol. 43, No. 17, 931-932, 2007.
doi:10.1049/el:20071074

7. Kim, P., G. Chaudhary, and Y. Jeong, "Analysis and design of a branch-line balun with high-isolation wideband characteristics," Wiley Microwave and Optical Technology Letters, Vol. 57, No. 5, May 2015.

8. Park, M.-J. and B. Lee, "Stubbed branch line balun," IEEE Microwave Wireless Components Letters, Vol. 17, 169-171, Mar. 2007.
doi:10.1109/LMWC.2006.890445

9. Velidi, V. K., A. Pal, and S. Sanyal, "Harmonics and size reduced microstrip branch line baluns using shunt open stubs," International Journal of RF and Microwave Computer-Aided Engg., Vol. 21, No. 2, 199-205, Mar. 2011.
doi:10.1002/mmce.20505

10. Velidi, V. K. and S. Sanyal, "Wide range suppressed harmonic response compact microstrip balun," International Journal of Electronics and Communications, Vol. 66, 45-48, 2012.
doi:10.1016/j.aeue.2011.04.012

11. Kumari, A., P. Bhowmik, and T. Moyra, "Design and validation of miniaturize rat race coupler based microstrip balun," International Journal of Electronics and Communications, Aug. 2018.

Dr. Vuppuloori Ravi Reddy

Dr. Vamsi Krishna Velidi

Dr. Bhima Prabhakara Rao