volume | PIER Journals

Abstract

A compact microstrip rat race attained by artificially shortening its lines by inserting stubs is presented. The design starts with a preliminary theoretical length reduction where quarter wavelength lines are shortened thanks to shunt open circuit stubs placed in the line mid-points. Such a preliminary design is then optimized via particle swarm optimization (PSO) within a full wave electromagnetic CAD, also bending the stubs to attain maximum compactness. The resulting design occupies an area up to only 37% of a conventional rat race, with performances comparable to those of a standard rat race.

1. Collin, R. E., Foundations for Microwave Engineering, John Wiley & Sons, 2007.

2. Pozar, D. M., Microwave Engineering, John Wiley & Sons, 2011.

3. Fooks, E. H. and R. A. Zakarevicius, Microwave Engineering Using Microstrip Circuits, Prentice-Hall, Inc., 1990.

4. Rao, P., Design of Wide Band Hybrid Coupler, LAP LAMBERT Academic Publishing, 2013.

5. Maddio, S., G. Pelosi, M. Righini, and S. Selleri, "Balanaced loaded transmission lines applied to hybrid couplers design," 2018 IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting, 947-948, IEEE, 2018.
doi:10.1109/APUSNCURSINRSM.2018.8608400

6. Maddio, S., G. Pelosi, M. Righini, and S. Selleri, "A novel hybrid coupler design based on the concept of balanced loaded transmission lines," 2019 IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting, 743-744, IEEE, 2019.
doi:10.1109/APUSNCURSINRSM.2019.8889137

7. Cidronali, A., S. Maddio, N. Giovannelli, and G. Collodi, "Frequency analysis and multiline implementation of compensated impedance inverter for wideband doherty high-power amplifier design," IEEE Transactions on Microwave Theory and Techniques, Vol. 64, No. 5, 1359-1372, 2016.
doi:10.1109/TMTT.2016.2549524

8. Maddio, S., G. Pelosi, M. Righini, and S. Selleri, "A multi-objective invasive weed optimization for broad band sequential rotation networks," 2018 IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting, 955-956, IEEE, 2018.
doi:10.1109/APUSNCURSINRSM.2018.8608713

9. Liu, G.-Q., L.-S. Wu, and W.-Y. Yin, "A compact microstrip rat-race coupler with modified lange and T-shaped arms," Progress In Electromagnetics Research, Vol. 115, 509-523, 2011.
doi:10.2528/PIER11032003

10. Liu, H., S.-J. Fang, Z. Wang, and Y. Zhou, "Miniaturization of trans-directional coupled line couplers using series inductors," Progress In Electromagnetics Research C, Vol. 46, 171-177, 2014.
doi:10.2528/PIERC13122201

11. Bernardi, P., R. Cicchetti, G. Pelosi, A. Reatti, S. Selleri, and M. Tatini, "An equivalent circuit for EMI prediction in printed circuit boards featuring a straight-to-bent microstrip line coupling," Progress In Electromagnetics Research B, Vol. 5, 107-118, 2008.
doi:10.2528/PIERB08020502

12. Selleri, S., M. Mussetta, P. Pirinoli, R. E. Zich, and L. Matekovits, "Some insight over new variations of the particle swarm optimization method," IEEE Antennas and Wireless Propagation Letters, Vol. 5, 235-238, 2006.
doi:10.1109/LAWP.2006.874071

13. Tseng, C.-H. and H.-J. Chen, "Compact rat-race coupler using shunt-stub-based artificial transmission lines," IEEE Microwave and Wireless Components Letters, Vol. 18, No. 11, 734-736, 2008.
doi:10.1109/LMWC.2008.2005225

14. Agastra, E., G. Pelosi, S. Selleri, and R. Taddei, "Multiobjective optimization techniques," Wiley Encyclopedia of Electrical and Electronics Engineering, 1-29, 2014.

15. Agastra, E., G. Pelosi, S. Selleri, and R. Taddei, "Taguchi's method for multi-objective optimization problems," International Journal of RF and Microwave Computer-Aided Engineering, Vol. 23, No. 3, 357-366, 2013.
doi:10.1002/mmce.20680

16. Pelosi, G., S. Selleri, and R. Taddei, "A novel multiobjective Taguchi's optimization technique for multibeam array synthesis," Microwave and Optical Technology Letters, Vol. 55, No. 8, 1836-1840, 2013.
doi:10.1002/mop.27705

17. Maddio, S., G. Pelosi, M. Righini, and S. Selleri, "A comparison between grey wolf and invasive weed optimizations applied to microstrip filters," 2019 IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting, 1033-1034, IEEE, 2019.
doi:10.1109/APUSNCURSINRSM.2019.8888446

18. Chuang, M.-L., "Miniaturized ring coupler of arbitrary reduced size," IEEE Microwave and Wireless Components Letters, Vol. 15, No. 1, 16-18, 2005.
doi:10.1109/LMWC.2004.840960

19. Mandal, M. K. and S. Sanyal, "Reduced-length rat-race couplers," IEEE Transactions on Microwave Theory and Techniques, Vol. 55, No. 12, 2593-2598, 2007.
doi:10.1109/TMTT.2007.910058

20. Gu, J. and X. Sun, "Miniaturization and harmonic suppression rat-race coupler using C-SCMRC resonators with distributive equivalent circuit," IEEE Microwave and Wireless Components Letters, Vol. 15, No. 12, 880-882, 2005.
doi:10.1109/LMWC.2005.859980

21. Okabe, H., C. Caloz, and T. Itoh, "A compact enhanced-bandwidth hybrid ring using an artificial lumped-element left-handed transmission-line section," IEEE Transactions on Microwave Theory and Techniques, Vol. 52, No. 3, 798-804, 2004.
doi:10.1109/TMTT.2004.823541

22. Eccleston, K. W. and S. H. Ong, "Compact planar microstripline branch-line and rat-race couplers," IEEE Transactions on Microwave Theory and Techniques, Vol. 51, No. 10, 2119-2125, 2003.
doi:10.1109/TMTT.2003.817442

23. Settaluri, R. K., G. Sundberg, A. Weisshaar, and V. Tripathi, "Compact folded line rat-race hybrid couplers," IEEE Microwave and Guided Wave Letters, Vol. 10, No. 2, 61-63, 2000.
doi:10.1109/75.843101

24. Kuo, J.-T., J.-S. Wu, and Y.-C. Chiou, "Miniaturized rat race coupler with suppression of spurious passband," IEEE Microwave and Wireless Components Letters, Vol. 17, No. 1, 46-48, 2007.
doi:10.1109/LMWC.2006.887254

25. Chen, C.-C. and C.-K. Tzuang, "Synthetic quasi-tem meandered transmission lines for compacted microwave integrated circuits," IEEE Transactions on Microwave Theory and Techniques, Vol. 52, No. 6, 1637-1647, 2004.
doi:10.1109/TMTT.2004.828468

26. Monti, G. and L. Tarricone, "Reduced-size broadband CRLH-ATL rat-race coupler," 2006 European Microwave Conference, 125-128, IEEE, 2006.
doi:10.1109/EUMC.2006.281216

27. Ghali, H. and T. A. Moselhy, "Miniaturized fractal rat-race, branch-line, and coupled-line hybrids," IEEE Transactions on Microwave Theory and Techniques, Vol. 52, No. 11, 2513-2520, 2004.
doi:10.1109/TMTT.2004.837154

28. Wang, C.-W., T.-G. Ma, and C.-F. Yang, "A new planar articial transmission line and its applications to a miniaturized butler matrix," IEEE Transactions on Microwave Theory and Techniques, Vol. 55, No. 12, 2792-2801, 2007.
doi:10.1109/TMTT.2007.909474

29. Maddio, S., A. Cidronali, M. Passaume, G. Collodi, and S. Maurri, "Fine-grained azimuthal direction of arrival estimation using received signal strengths," Electronics Letters, Vol. 53, No. 10, 687-689, 2017.
doi:10.1049/el.2017.0456

Dr. Stefano Maddio

Dr. Giuseppe Pelosi

Dr. Monica Righini

Professor Stefano Selleri