volume | PIER Journals

Abstract

Existing wideband circularly polarized (CP) antennas generally face trade-offs among wide impedance bandwidth, broad axial ratio (AXR) bandwidth, gain, and compactness in single-layer implementation. Furthermore, a number of reported designs are multi-layer or metasurface-based or require complex feeding networks, making them more complex to manufacture, resulting in increased fabrication costs. In this paper, we develop a wideband circularly polarized (CP) antenna design using an active central patch with four parasitic patches on an FR4 substrate. The CP condition is obtained by exciting two orthogonal modes of equal magnitude and $90^\circ$ phase difference, which are attained by perturbing the active patch and placing a diagonal coaxial feed on it. We enhance the broadside gain and bandwidth by loading parasitic patches around the active patch via electromagnetic coupling. This type of coupling improves aperture efficiency, impedance matching, and axial ratio bandwidth (ARBW). Characteristic Mode Analysis (CMA) is used to determine and optimize the dominant orthogonal modes responsible for circular polarization and radiation enhancement. The fabricated prototype shows a measured -10 dB impedance bandwidth (IBW) of 18.12% (5.42-6.50 GHz), an ARBW of 17.87% (5.35-6.40 GHz), and a broadside gain of 8.5 dBi. The measured and simulated results show excellent agreement, confirming the functionality of the designed antenna. The antenna's compact size, wide bandwidth, and high broadside gain make it a potential solution for broadband wireless communication, satellite-based systems, and C-band antenna applications.

1. Bag, Biplab, Rahul Mondal, Sushanta Biswas, and Partha Pratim Sarkar, "Application-based evolution of microstrip antenna: Presenting wide-bandwidth circular polarization and multi-resonating characteristics," Journal of Electromagnetic Waves and Applications, Vol. 34, No. 14, 1899-1917, 2020.
doi:10.1080/09205071.2020.1796823 Google Scholar

2. Hussain, Niamat, Huy Hung Tran, and Tuan Tu Le, "Single-layer wideband high-gain circularly polarized patch antenna with parasitic elements," AEU --- International Journal of Electronics and Communications, Vol. 113, 152992, 2020.
doi:10.1016/j.aeue.2019.152992 Google Scholar

3. Suyan, Nitin Kumar, Fateh Lal Lohar, Yogesh Solunke, and Chandresh Dhote, "Design of compact size tri-band stacked patch antenna for GPS and IRNSS applications," Congress on Intelligent Systems, 501-509, Springer, Singapore, 2020.
doi:10.1007/978-981-33-4582-9_39

4. Maurya, Rakesh Kumar, Binod K. Kanaujia, A. K. Gautam, S. Chatterji, and Anil Kumar Singh, "Circularly polarized hexagonal ring microstrip patch antenna with asymmetrical feed and DGS," Microwave and Optical Technology Letters, Vol. 62, No. 4, 1702-1708, 2020.
doi:10.1002/mop.32220 Google Scholar

5. Xu, Hengfei, Jianyi Zhou, Ke Zhou, and Zhiqiang Yu, "Low-profile circularly polarised patch antenna with high gain and conical beam," IET Microwaves, Antennas & Propagation, Vol. 12, No. 7, 1191-1195, 2018.
doi:10.1049/iet-map.2017.0928 Google Scholar

6. Shaw, Murari, Niranjan Mandal, and Malay Gangopadhyay, "A compact circularly polarized isosceles triangular microstrip patch antenna with parasitic elements for multiband application," Microwave and Optical Technology Letters, Vol. 62, No. 10, 3275-3282, 2020.
doi:10.1002/mop.32445 Google Scholar

7. Rashmi, Ashok Kumar, Kapil Saraswat, and Arjun Kumar, "Wideband circularly polarized parasitic patches loaded coplanar waveguide-fed square slot antenna with grounded strips and slots for wireless communication systems," AEU --- International Journal of Electronics and Communications, Vol. 114, 153011, 2020.
doi:10.1016/j.aeue.2019.153011 Google Scholar

8. Tran, H., Phuong Kim-Thi, Nguyen Tran, Thao Hoang-Thi-Phuong, and Yem Vu-Van, "A novel approach to design compact, wideband, and high-gain circularly polarized MIMO antenna using dual-polarized elements and hybrid couplers," Scientific Reports, Vol. 15, No. 1, 45100, 2025.
doi:10.1038/s41598-025-32097-5 Google Scholar

9. Du, Kaiwen, Zhenlong Huang, Xueru Xu, Jianqiang Hao, Quanhao Pang, and Jun Ouyang, "A wideband dual-port selectable RHCP/LHCP polarized antenna for satellite communications," IEEE Antennas and Wireless Propagation Letters, 1-5, 2026.
doi:10.1109/lawp.2026.3711159 Google Scholar

10. Shrivastava, Manoj Kumar, Ripudaman Singh, Diptiranjan Samantaray, Azharuddin Khan, Anil Kumar Gautam, and Amit Kumar Singh, "A metamaterial loaded high gain low profile RHCP microstrip antenna for X-band applications," IEEE Access, Vol. 13, 33321-33329, 2025.
doi:10.1109/access.2025.3542460 Google Scholar

11. Deng, Zhuolin, Jianbin Li, Huanhuan Peng, Qi Zou, Pei Xiao, and Gaosheng Li, "Compact dual-mode CP antenna with wide AR beamwidths for BDS-based vehicular applications," IEEE Open Journal of Antennas and Propagation, Vol. 7, No. 3, 838-848, 2026.
doi:10.1109/ojap.2026.3664692 Google Scholar

12. Sridhar, P. and R. Poonkuzhali, "A dual-band circular polarized CPW fed low-profile antenna for WLAN and X-band applications," Results in Engineering, Vol. 27, 106466, 2025.
doi:10.1016/j.rineng.2025.106466 Google Scholar

13. Jash, Shyam Sundar, Chiranjib Goswami, and Rowdra Ghatak, "A low profile broadband circularly polarized planar antenna with an embedded slot realized on a reactive impedance surface," AEU --- International Journal of Electronics and Communications, Vol. 108, 62-72, 2019.
doi:10.1016/j.aeue.2019.06.006 Google Scholar

14. Li, Zijie, Yuechen Liu, Mengfei Zhao, Weihua Zong, and Shi He, "A wideband circularly polarized metasurface antenna with high gain using characteristic mode analysis," Electronics, Vol. 14, No. 14, 2818, 2025.
doi:10.3390/electronics14142818 Google Scholar

15. Yousef, Basma M., Allam M. Ameen, Meshari D. Alanazi, Maheswar Rajagopal, and Ahmed A. Ibrahim, "A wide-band antenna with circular polarization utilizing a U-shaped radiator and parasitic strip for wireless communications," Micromachines, Vol. 14, No. 7, 1308, 2023.
doi:10.3390/mi14071308 Google Scholar

16. Obeng Kwakye, Kingsford Sarkodie, Nouman Rasool, Kwame Oteng Gyasi, Joseph Abroquah, Mubarak Sani Ellis, Ohemeng Lord Owusu, Abdul-Rahman Ahmed, and Jerry John Kponyo, "Design and analysis of a low-profile dual-band circularly polarized monopole antenna based on characteristic mode analysis," International Journal of RF and Microwave Computer-Aided Engineering, Vol. 2023, No. 1, 7855907, 2023.
doi:10.1155/2023/7855907 Google Scholar

17. Chen, Zhensheng, Xuezhi Zheng, Chaoyun Song, Jiahao Zhang, Vladimir Volskiy, Yifan Li, and Guy A. E. Vandenbosch, "Enhancing circular polarization performance of low-profile patch antennas for wearables using characteristic mode analysis," Sensors, Vol. 23, No. 5, 2474, 2023.
doi:10.3390/s23052474 Google Scholar

18. Li, Haixuan, Rui Zhang, Lu Tian, Bingchuan Xie, Zhaomeng Zhu, and Yueyan Ren, "Design of low-profile broadband circularly polarized flat-top metasurface antenna," Journal of Physics D: Applied Physics, Vol. 58, No. 26, 265105, 2025.
doi:10.1088/1361-6463/ade5fe Google Scholar

19. Nakamura, Teruhisa and Takeshi Fukusako, "Broadband design of circularly polarized microstrip patch antenna using artificial ground structure with rectangular unit cells," IEEE Transactions on Antennas and Propagation, Vol. 59, No. 6, 2103-2110, 2011.
doi:10.1109/tap.2011.2143656 Google Scholar

20. Ding, Chang, Rigeng Wu, and Jian Dong, "Characteristic mode inspired circular polarization antenna using metamaterial," 2021 International Applied Computational Electromagnetics Society (ACES-China) Symposium, 1-2, Chengdu, China, 2021.
doi:10.23919/aces-china52398.2021.9581434

21. Lohar, Fateh Lohar, Indra Bhooshan Sharma, Virender Katewa, and Mahendra Mohan Sharma, "T-shaped tri-band antenna based on characteristic mode analysis for satellite applications," Progress In Electromagnetics Research C, Vol. 115, 65-80, 2021.
doi:10.2528/pierc21072203 Google Scholar

22. Sharma, Indra Bhooshan, Fateh Lal Lohar, Prachi Joshi, Joohi Garg, and M. M. Sharma, "Multi-band antenna design by reshaping surface currents of higher order mode using CMA method," IETE Journal of Research, Vol. 70, No. 6, 5572-5582, 2024.
doi:10.1080/03772063.2023.2274908 Google Scholar

23. Balanis, C. A., Antenna Theory: Analysis and Design, John Wiley & Sons, 2016.

24. Chang, Lei, Ling-Lu Chen, Jian-Qiang Zhang, and Dan Li, "A wideband circularly polarized antenna with characteristic mode analysis," International Journal of Antennas and Propagation, Vol. 2020, No. 1, 5379892, 2020.
doi:10.1155/2020/5379892 Google Scholar

25. Lohar, Fateh Lal, Chandresh Dhote, Yogesh Solunke, and Nitin Kumar Suyan, "Design of circularly polarized irnss receiver antenna using characteristic mode analysis," 2019 IEEE Indian Conference on Antennas and Propogation (InCAP), 1-5, Ahmedabad, India, 2019.
doi:10.1109/incap47789.2019.9134508

26. Yeung, Sai Ho and Chao-Fu Wang, "Study of a parasitic U‐slot patch array antenna with characteristic mode analysis," Microwave and Optical Technology Letters, Vol. 60, No. 2, 482-488, 2018.
doi:10.1002/mop.30992 Google Scholar

27. Ayn, Qurratul, S. Yuvaraj, and Kiran Kumar Gurrala, "Design and analysis of low-profile dual-band circularly polarized antenna using CMA for wearable applications," Sādhanā, Vol. 50, No. 3, 185, 2025.
doi:10.1007/s12046-025-02863-2 Google Scholar

28. Dhara, Reshmi, "Design of a miniaturized CPW fed Z-shaped monopole antenna using theory of characteristics modes for bandwidth enhancement," Sādhanā, Vol. 46, No. 2, 87, 2021.
doi:10.1007/s12046-021-01610-7 Google Scholar

29. Wu, Jianjun, Yingzeng Yin, Zedong Wang, and Ruina Lian, "Broadband circularly polarized patch antenna with parasitic strips," IEEE Antennas and Wireless Propagation Letters, Vol. 14, 559-562, 2014.
doi:10.1109/lawp.2014.2373823 Google Scholar

30. Yang, Hongcai, Xiongying Liu, and Yi Fan, "Design of broadband circularly polarized all-textile antenna and its conformal array for wearable devices," IEEE Transactions on Antennas and Propagation, Vol. 70, No. 1, 209-220, 2022.
doi:10.1109/tap.2021.3098542 Google Scholar

31. Hu, Xiaomu, Sen Yan, Jiahao Zhang, Vladimir Volski, and Guy A. E. Vandenbosch, "Omni-directional circularly polarized button antenna for 5 GHz WBAN applications," IEEE Transactions on Antennas and Propagation, Vol. 69, No. 8, 5054-5059, 2021.
doi:10.1109/tap.2021.3070896 Google Scholar

32. Mir, Reyhane, Hamideh Dashti, and Javad Ahmadi-Shokouh, "Design and analysis of circularly polarized circular patch antenna with multiple shorting pins using characteristic mode theory," AEU --- International Journal of Electronics and Communications, Vol. 146, 154112, 2022.
doi:10.1016/j.aeue.2022.154112 Google Scholar

33. Jhajharia, Tejpal, Vivekanand Tiwari, Dinesh Yadav, Sanyog Rawat, and Deepak Bhatnagar, "Wideband circularly polarised antenna with an asymmetric meandered-shaped monopole and defected ground structure for wireless communication," IET Microwaves, Antennas & Propagation, Vol. 12, No. 9, 1554-1558, 2018.
doi:10.1049/iet-map.2018.0092 Google Scholar

34. Jhajharia, Tejpal, Vivekanand Tiwari, Deepak Bhatnagar, Dinesh Yadav, and Sanyog Rawat, "A dual-band CP dual-orthogonal arms monopole antenna with slanting edge DGS for C-band wireless applications," AEU --- International Journal of Electronics and Communications, Vol. 84, 251-257, 2018.
doi:10.1016/j.aeue.2017.12.005 Google Scholar

35. Jhajharia, Tejpal, Vivekanand Tiwari, and Deepak Bhatnagar, "Polarisation reconfigurable dual-band circularly polarised patch antenna with defected ground plane for C-band wireless applications," IET Microwaves, Antennas & Propagation, Vol. 13, No. 14, 2551-2558, 2019.
doi:10.1049/iet-map.2018.6214 Google Scholar

Dr. Sagar Babanrao Pokharkar

Dr. Kanchan Tiwari