volume | PIER Journals

Abstract

This paper presents a compact, funnel-shaped, MIMO antenna for ultra-wideband (UWB) applications. The antenna element consists of a top funnel-shaped patch and a bottom rectangular ground plane. By using an elliptical slot on the patch and a slit at the center of the ground plane, impedance matching is effectively improved, and bandwidth is significantly expanded. Meanwhile, by etching a slot at the center of the ground plane and introducing semicircular and T-shaped parasitic stubs, the mutual coupling between the antenna elements is successfully suppressed. The overall dimension of the antenna is 48 × 27 × 1.6 mm³. The simulated and measured results exhibit excellent agreement, demonstrating that the antenna achieves a continuous impedance bandwidth covering 3.16-16.48 GHz, which corresponds to a fractional bandwidth of 135.64%. Across the entire operating band, the port isolation exceeds 20 dB; the radiation efficiency ranges from 73.4% to 92.6%; the envelope correlation coefficient (ECC) is below 0.0025; and the diversity gain (DG) is better than 9.9982 dB. Combining ultra-wide bandwidth, high isolation, and extremely low channel correlation, the proposed antenna provides a reliable solution for high-performance UWB-MIMO communication systems.

1. Sharbati, Vahid, Xiulong Bao, John J. Healy, Nan Zhang, Khatereh Nadali, and Max J. Ammann, "Dynamic tuning of notch bands in UWB antenna based on liquid metal for cognitive radio applications," IEEE Antennas and Wireless Propagation Letters, Vol. 23, No. 12, 4708-4712, 2024.
doi:10.1109/lawp.2024.3466613 Google Scholar

2. Nejdi, Ibrahime Hassan, Mohamed Marzouk, Mustapha Ait Lafkih, Seddik Bri, Jamal Abdul Nasir, Zahriladha Zakaria, and Ahmed Jamal Abdullah Al-Gburi, "A low-profile UWB monopole antenna and high-isolated UWB-MIMO antenna for wireless communications networks," Progress In Electromagnetics Research C, Vol. 161, 105-119, 2025.
doi:10.2528/pierc25082106 Google Scholar

3. Jayant, Shailesh, Garima Srivastava, and Sachin Kumar, "Quad-port UWB MIMO footwear antenna for wearable applications," IEEE Transactions on Antennas and Propagation, Vol. 70, No. 9, 7905-7913, 2022.
doi:10.1109/tap.2022.3177481 Google Scholar

4. Nie, Li Ying, Xian Qi Lin, Zi Qiang Yang, Jin Zhang, and Bao Wang, "Structure-shared planar UWB MIMO antenna with high isolation for mobile platform," IEEE Transactions on Antennas and Propagation, Vol. 67, No. 4, 2735-2738, 2019.
doi:10.1109/tap.2018.2889596 Google Scholar

5. Jayant, Shailesh and Garima Srivastava, "Close-packed quad-element triple-band-notched UWB MIMO antenna with upgrading capability," IEEE Transactions on Antennas and Propagation, Vol. 71, No. 1, 353-360, 2023.
doi:10.1109/tap.2022.3222768 Google Scholar

6. El Atrash, Mohamed, Mennaalla S. Khalil, Waad A. Mahmoud, and Mahmoud A. Addalla, "A low-profile fully-fabric high isolation dual-port MIMO antenna for UWB wearable applications," IEEE Transactions on Antennas and Propagation, Vol. 74, No. 5, 3971-3979, 2026.
doi:10.1109/tap.2026.3659993 Google Scholar

7. Li, Wanwan, Ling Wu, Shengqiang Li, Xia Cao, and Bing Yang, "Bandwidth enhancement and isolation improvement in compact UWB-MIMO antenna assisted by characteristic mode analysis," IEEE Access, Vol. 12, 17152-17163, 2024.
doi:10.1109/access.2024.3357629 Google Scholar

8. Nie, Li Ying, Xian Qi Lin, Shang Xiang, Bao Wang, Long Xiao, and Jun Yong Ye, "High-isolation two-port UWB antenna based on shared structure," IEEE Transactions on Antennas and Propagation, Vol. 68, No. 12, 8186-8191, 2020.
doi:10.1109/tap.2020.2997461 Google Scholar

9. Mohammed, Jafar Ramadhan, "Design of printed Yagi antenna with additional driven element for WLAN applications," Progress In Electromagnetics Research C, Vol. 37, 67-81, 2013.
doi:10.2528/pierc12121201 Google Scholar

10. Luo, Chao-Ming, Jing-Song Hong, and Lin-Lin Zhong, "Isolation enhancement of a very compact UWB-MIMO slot antenna with two defected ground structures," IEEE Antennas and Wireless Propagation Letters, Vol. 14, 1766-1769, 2015.
doi:10.1109/lawp.2015.2423318 Google Scholar

11. Iqbal, Amjad, Omar A. Saraereh, Arbab Waheed Ahmad, and Shahid Bashir, "Mutual coupling reduction using F-shaped stubs in UWB-MIMO antenna," IEEE Access, Vol. 6, 2755-2759, 2018.
doi:10.1109/access.2017.2785232 Google Scholar

12. Chen, Zhijian, Weisi Zhou, and Jingsong Hong, "A miniaturized MIMO antenna with triple band-notched characteristics for UWB applications," IEEE Access, Vol. 9, 63646-63655, 2021.
doi:10.1109/access.2021.3074511 Google Scholar

13. Zhang, Shuai and Gert Frølund Pedersen, "Mutual coupling reduction for UWB MIMO antennas with a wideband neutralization line," IEEE Antennas and Wireless Propagation Letters, Vol. 15, 166-169, 2016.
doi:10.1109/lawp.2015.2435992 Google Scholar

14. Zheng, Xuemei, Linfei Yue, and Yunan Zhang, "A compact four-port axially symmetric UWB-MIMO antenna array: Metamaterial-integrated coplanar waveguide for broadband operation with high isolation," Progress In Electromagnetics Research C, Vol. 162, 58-69, 2025.
doi:10.2528/pierc25100105 Google Scholar

15. Mohammed, Jafar Ramadhan and Dalia Ahmad Al-Khafaf, "Optimizing performance of antenna arrays with clustered fractal shapes for multiband applications," Journal of Telecommunications and Information Technology, Vol. 95, No. 1, 91-96, 2024.
doi:10.26636/jtit.2024.1.1456 Google Scholar

16. Wang, Zhonggen, Guoxiang Song, Wenyan Nie, Ming Yang, Chenlu Li, and Mingqing Wang, "A racket-like UWB MIMO antenna with high isolation," Progress In Electromagnetics Research C, Vol. 144, 159-168, 2024.
doi:10.2528/pierc24052901 Google Scholar

17. Potti, Devisowjanya, Yarasi Tusharika, Mohammed Gulam Nabi Alsath, Savarimuthu Kirubaveni, Malathi Kanagasabai, Radha Sankararajan, Santosh Narendhiran, and P. Balaji Bhargav, "A novel optically transparent UWB antenna for automotive MIMO communications," IEEE Transactions on Antennas and Propagation, Vol. 69, No. 7, 3821-3828, 2021.
doi:10.1109/tap.2020.3044383 Google Scholar

18. Rajesh, G. and R. Poonkuzhali, "Design and analysis of CPW fed ultrathin flexible MIMO antenna for UWB and X-band applications," IEEE Access, Vol. 12, 96704-96717, 2024.
doi:10.1109/access.2024.3426592 Google Scholar

19. Mazzinghi, Agnese, David Barras, Boris Danev, and Angelo Freni, "Miniaturized UWB dual-port antenna for localization applications," IEEE Antennas and Wireless Propagation Letters, Vol. 23, No. 3, 1080-1084, 2024.
doi:10.1109/lawp.2023.3344593 Google Scholar

20. Kamal, Mian Muhammad, Binghao Wang, Nosherwan Shoaib, Umair Rafique, Muhammad Inam Abbasi, and Muhammad Ramlee Kamarudin, "Self-decoupled quad-port CPW-fed fractal MIMO antenna with UWB characteristics," International Journal of Antennas and Propagation, Vol. 2024, No. 1, 3826899, 2024.
doi:10.1155/ijap/3826899 Google Scholar

21. Srivastava, Garima, Mohammad Al-Hamami, Sachin Kumar, Om Prakash Kumar, et al. "Triple-band notched and highly decoupled MIMO antenna using characteristic mode analysis," IEEE Access, Vol. 13, 165956-165969, 2025.
doi:10.1109/access.2025.3611809 Google Scholar

Dr. Shanhua Yao

Dr. Yuting Wang

Professor Zhonggen Wang

Professor Han Lin