Circularly polarized antenna using ground-mode tuning technique for small-sized IoT devices

ABSTRACT

This study focuses on the generation of circular polarization (CP) in a small-sized ground plane by using ground-mode tuning (GMT) technique. The proposed antenna is composed of two branches, so that it can simultaneously excite two orthogonal modes of the ground plane for radiation. Two metal strips at the ends of the ground plane are adopted as GMT structures, and the dominant modes along the length and width of the ground plane can be controlled by tuning the property of the shorting pins, conveniently. Both simulation and measurement results indicate that the proposed technique can achieve a wideband impedance bandwidth and a sufficient AR bandwidth. Furthermore, the proposed CP antenna provides a less directive radiation pattern compared to a linearly-polarized antenna, which can be attractive in receiving performance.

KEYWORDS:

• Circular polarization
• ground-mode tuning
• orthogonal modes

ORCID

Longyue Qu http://orcid.org/0000-0001-5152-091X

Additional information

Funding

This work was supported by China Scholarship Council.

Notes on contributors

Haiyan Piao

Haiyan Piao received her BSc degree in communication engineering from Yanbian University, China, in 2013, and the MSc degree in microwave engineering from Hanyang University, Seoul, Rep. of Korea, in 2017. Her research interests are antenna design, MIMO, 5G communications, IoT, etc.

Guohui Dong

Guohui Dong is currently a technician in China United Network Communications Group Co., Ltd, China.

Longyue Qu

Longyue Qu received his BSc degree in communication engineering from Yanbian University, China, in 2013, and the MSc and PhD degrees from Hanyang University, Seoul, Rep. of Korea, in 2015 and 2018, respectively, in microwave engineering. He is currently a research fellow at Hanyang University. His current research interests include antenna theory and design especially for 4G/5G communications, massive MIMO, metamaterials, mmWave, and RF circuits. He serves as a reviewer for several international journals, such as IEEE Transactions on Antennas and Propagation, IEEE Antennas and Wireless Propagation Letters, and IEEE Access.