Squint-less arc array for near-field focusing in wideband systems

Abstract

In this paper, the arc array for squint-less near-field focusing is used, theoretically analyzed, and verified. The arc array is designed to overcome the squint phenomenon in the near-field and transfers the maximum power at a focused distance. The implemented transmitter is composed of $16\times 1$ vivaldi antennas with a $0.7\lambda$ spacing and operates at a frequency of 5.8 GHz. In addition, the design method of the arc array is proposed, considering the focused distances. In the experiments, the bending degree of the arc array is ${4.14}^{\circ }$ when the focused distance is 0.5 m. At a fractional bandwidth of 27.5%, the focus position is shifted 32%. On the other hand, in the arc array, the focus position is not shifted. Experimental results from the implemented arc array show good agreement with the proposed theory.

Keywords:

• Squint-less
• near-field focus
• retro-directive array
• arc array

Acknowledgments

This work was partially supported by the Research Project for Senior Researcher from the National Research Foundation of Korea (NRF) (No. 2020R1A2B5B02001696), and the Development of Civil Military Technology Project (No. 17-CM-MC-08) from the Institute of Civil Military Technology Cooperation (ICMTC).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was partially supported by the Research Project for Senior Researcher from the National Research Foundation of Korea (NRF) [grant number 2020R1A2B5B02001696], and the Development of Civil Military Technology Project [grant number 17-CM-MC-08] from the Institute of Civil Military Technology Cooperation (ICMTC).

Notes on contributors

Sol Kim

Sol Kim received the B.S in radio engineering from Chungnam National University (CNU), in 2018 and M.S in electrical engineering from the Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea, in 2020. He is currently working toward Ph.D. degree in electrical engineering from Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea. His current research interests include microwave power transmission (MPT), near-field beamforming, RADAR system and signal processing, RF system applications and antenna design.

Jeong-Wook Kim

Jeong-Wook Kim received the B.S. degree in electronics engineering from Pusan National University (PNU), Busan, South Korea, in 2018, and M.S. degree in electronics and electrical engineering from the Korea Advanced Institute of Science and Technology (KAIST) in 2020. He is currently working toward Ph.D. degree in electronics and electrical engineering from KAIST. His current research interests include RADAR system and signal processing, active phased array antenna system, wireless power charging system, invisible antenna.

Hyunyoung Cho

Hyunyoung Cho received the B.S., and M.S. degrees in electrical engineering form the Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea, in 2018, 2020, respectively, where she is currently pursuing the Ph.D. degree. Her research interests include phased array system, antenna design, wireless communicaiton systems, radar systems, and millimeter-wave RF systems.

ByungKuon Ahn

ByungKuon Ahn received the B.S. degreein electronic and electrical engineering from Sungkyunkwan University (SKKU), Suwon, South Korea, in 2015, and the M.S. degree in electrical engineering from the Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea, in 2017, where he is currently pursuing the Ph.D. degree in electrical engineering. His current research interests include phased array antenna design, multiple-input and multiple-output (MIMO) systems, and wireless communication systems.

Kwang-Seok Kim

Kwang-Seok Kim received the B.S. degree in electrical engineering from SoongSil University, Seoul, South Korea in 2013, and the M.S. degrees in electrical engineering from Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea, in 2013 and 2015. From 2015 to 2018, he worked at Samsung Electronics Semiconductor R&D center. He is currently pursuing the Ph.D. degree in electrical engineering from Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea. His research interest include signal integrity (SI), power integrity (PI), EMI/EMC, RF system applications, and antenna design.

Jong-Won Yu

Jong-Won Yu received the B.S., M.S., and Ph.D. degrees in electronic engineering from Korea Advanced Institution Science and Technology (KAIST), Daejeon, Republic of Korea in 1992,1994, and 1998, respectively. From 1995 to 2000, he worked at Samsung Electronics. He also served Wide Tecom Head and Telson, from 2000 to 2001 and from 2001 to 2004, respectively. In February 2004, he joined as an Assistant Professor with electrical engineering at KAIST, where since February 2006. In February 2006, he worked as an Associate Professor with electrical engineering at KAIST, where since February 2014, he has been a Professor at KAIST. His research interests emphasize millimeter wave circuit and system, wireless power transfer system, wireless/near- eld communication system, and RADAR system.