Wideband designs of proximity fed regular shape microstrip antennas using bow-tie and H-shape ground plane profile are proposed in 1000 MHz frequency range. The modified ground plane alters the quality factor of the patch cavity which enhances the impedance bandwidth. In terms of the results obtained for bandwidth and gain together, circular and square patches backed by bow-tie shape ground plane, followed by circular patch backed by H-shape ground plane yield optimum results. For substrate thickness of 0.097λg, against the conventional ground plane, bow-tie shape gives 12% and 24% bandwidth increment for circular and square patches, respectively, and H-shape ground plane yields bandwidth increment by 17% in circular patch. All these wideband designs offer peak gain around 6 dBi with a broadside radiation pattern. Further, modified ground plane profile helps in optimizing the proximity fed antennas on lower substrate thicknesses. Amongst all the configurations, for ~0.03λg reduction in the substrate thickness, SMSA using bow-tie shape ground plane yields 19% increase in the impedance bandwidth against the equivalent thicker substrate design with a peak broadside gain of above 6 dBi. Thus, proposed modified ground plane antennas yields bandwidth improvement but for a smaller substrate thickness.
2. Vandenbosch, G. A. E. and A. R. Van de Capelle, "Study of the capacitively fed microstrip antenna element," IEEE Transactions on Antennas and Propagation, Vol. 42, No. 12, 1648-1652, December 1994.
doi:10.1109/8.362807
3. Cheng, Cheng, Z. Du, and D. Huang, "A differentially fed broadband multimode microstrip antenna," IEEE Antennas and Wireless Propagation Letters, Vol. 19, No. 5, 771-775, March 2020.
doi:10.1109/LAWP.2020.2979492
4. Yoo, J. U. and H. W. Son, "A simple compact wideband microstrip antenna consisting of three staggered patches," IEEE Antennas and Wireless Propagation Letters, Vol. 19, No. 12, 2038-2042, September 2020.
doi:10.1109/LAWP.2020.3021491
5. Yang, D., H. Zhai, C. Guo, and H. Li, "A compact single-layer wideband microstrip antenna with filtering performance," IEEE Antennas and Wireless Propagation Letters, Vol. 19, No. 5, 801-805, March 2020.
doi:10.1109/LAWP.2020.2980631
6. Radavaram, S. and M. Pour, "Wideband radiation reconfigurable microstrip patch antenna loaded with two inverted U-Slots," IEEE Transactions on Antennas and Propagation, Vol. 67, No. 3, 1501-1508, December 2018.
doi:10.1109/TAP.2018.2885433
7. Guo, Y. X., K. M. Luk, K. F. Lee, and Y. L. Chow, "Double U-slot rectangular patch antenna," Electronics Letters, Vol. 34, No. 19, 1805-1806, September 1998.
doi:10.1049/el:19981283
8. Zhang, X., K. D. Hong, L. Zhu, X. K. Bi, and T. Yuan, "Wideband differentially-fed patch antennas under dual high-order modes for stable high gain," IEEE Transactions on Antennas and Propagation, Vol. 69, No. 1, 1-5, July 2020.
9. Tiwari, R. N., P. Singh, and B. K. Kanaujia, "Butter fly shape compact microstrip antenna for wideband applications," Progress In Electromagnetics Research Letters, Vol. 69, 45-50, 2017.
doi:10.2528/PIERL17042703
10. Wu, Z. F., W. J. Lu, J. Yu, and L. Zhu, "Wideband null frequency scanning circular sector patch antenna under triple resonance," IEEE Transactions on Antennas and Propagation, Vol. 68, No. 11, 7266-7274, May 2020.
doi:10.1109/TAP.2020.2995459
11. Lu, W. J., Q. Li, S. G. Wang, and L. Zhu, "Design approach to a novel dual-mode wideband circular sector patch antenna," IEEE Transactions on Antennas and Propagation, Vol. 65, No. 10, 4980-4990, July 2017.
doi:10.1109/TAP.2017.2734073
12. Mandal, K. and P. P. Sarkar, "High gain wide-band U-shaped patch antennas with modified ground planes," IEEE Transactions on Antennas and Propagation, Vol. 61, No. 4, 2279-2282, January 2013.
doi:10.1109/TAP.2012.2233455
13. Mondal, K. and P. P. Sarkar, "Half hexagonal broadband high gain microstrip patch antenna for mobile and radar applications," Microwave and Optical Technology Letters, Vol. 58, No. 5, 1028-1032, May 2016.
doi:10.1002/mop.29726
14. Mondal, K. and P. P. Sarkar, "M-shaped broadband microstrip patch antenna with modified ground plane," Microwave and Optical Technology Letters, Vol. 57, No. 6, 1308-1312, June 2015.
doi:10.1002/mop.29068
15. Bhatia, S. S., A. Sahni, and S. B. Rana, "A novel design of compact monopole antenna with defected ground plane for wideband applications," Progress In Electromagnetics Research M, Vol. 70, 21-31, 2018.
doi:10.2528/PIERM18050201
16., IE3D Software, Version 12.
17. Kadam, P. A. and A. A. Deshmukh, "Modified ground plane multi-band rectangular microstrip antennas with reduced cross polar radiation," Progress In Electromagnetics Research C, Vol. 100, 59-71, 2020.
doi:10.2528/PIERC19122202
18. Kadam, P. A. and A. A. Deshmukh, "Designs of regular shape microstrip antennas backed by bow-tie shape ground plane for enhanced antenna characteristics," AEU-International Journal of Electronics and Communications, Vol. 137, 1-9, 2021.
19. Jyoti Gogoi, P., D. Jyoti Gogoi, and N. S. Bhattacharyya, "Modified ground plane of patch antenna for broadband applications in C-band," Microwave and Optical Technology Letters, Vol. 58, No. 5, 1074-1078, May 2016.
doi:10.1002/mop.29724
20. Kandwal, A., R. Sharma, and S. K. Kumar, "Bandwidth enhancement using Z-shaped defected ground structure for a microstrip antenna," Microwave and Optical Technology Letters, Vol. 55, No. 10, 2251-2254, October 2013.
doi:10.1002/mop.27836
21. Wong, K. L., C. L. Tang, and J. Y. Chiou, "Broadband probe-fed patch antenna with a W-shaped ground plane," IEEE Transactions on Antennas and Propagation, Vol. 50, No. 6, 827-831, August 2002.
doi:10.1109/TAP.2002.1017663
22. Hsu, W. H. and K. L. Wong, "Broadband probe-fed patch antenna with a U-shaped ground plane for cross-polarization reduction," IEEE Transactions on Antennas and Propagation, Vol. 50, No. 3, 352-355, August 2002.
doi:10.1109/8.999626
23. Huang, J., "The finite ground plane effects on the microstrip antenna radiation patterns," IEEE Transactions on Antennas and Propagation, Vol. 31, No. 4, 649-653, July 1983.
doi:10.1109/TAP.1983.1143108
24. Noghanian, S. and L. Shafai, "Control of microstrip antenna radiation characteristics by ground plane size and shape," IEE Proceedings Microwave Antennas and Propagation, Vol. 145, No. 3, 207-212, June 1998.
doi:10.1049/ip-map:19981819
25. Rajo-Iglesias, E., L. Inclán-Sánchez, and Ó. Quevedo-Teruel, "Back radiation reduction in patch antennas using planar soft surfaces," Progress In Electromagnetics Research Letters, Vol. 6, 123-130, 2009.
doi:10.2528/PIERL08111202
26. Lee, H. M. and W. S Choi, "Effect of partial ground plane removal on the radiation characteristics of a microstrip antenna," Wireless Engineering and Technology, Vol. 4, 5-12, 2013.
doi:10.4236/wet.2013.41002
27. Alias, H., M. T. Ali, S. Subahir N. Ramli, M. A. Sulaiman, and S. Kayat, "A back lobe reduction of aperture coupled microstrip antenna using DGS," Proceedings of 10th International Conference on Electrical Engineering/Electronics, Computer, Telecommunications and Information, Thailand, May 15-17, 2013, DOI: 10.1109/ECTICon.2013.6559514.
28. Chen, Y., S. Yang, and Z. Nie, "Bandwidth enhancement method for low profile E-shaped microstrip patch antennas," IEEE Transactions on Antennas and Propagation, Vol. 58, No. 7, 2442-2447, 2010.
doi:10.1109/TAP.2010.2048850
29. Oka, N. C. M., T. Uchida, and S. Nitta, "Influence of ground plane width on reduction of radiated emission from printed circuit boards," Electronics and Communications in Japan, Part 2, Vol. 84, No. 1, 21-31, 2001.
doi:10.1002/1520-6432(200101)84:1<21::AID-ECJB3>3.0.CO;2-P
30. Watanabe, T., O. Wada, T. Miyashita, and R. Koga, "Common mode current generation caused by difference of unbalance of transmission lines on a printed circuit board with narrow ground pattern," IEICE Trans. Communication, Vol. E83-B, No. 3, 593-599, March 2000.