Reconfigurable narrow open-slot LTE MIMO antennas for metal-rimmed smartphone applications

Abstract

This paper presents a ‘reconfigurable narrow open-slot LTE MIMO antennas for metal-rimmed smartphone applications,’ which consist of two structurally identical L-shaped slot antennas combined with a metal rim with a 1 mm wide opening. The slots are 3 mm wide and 90 mm long, and are placed diagonally on the upper left and lower right corners of the mobile phone in a mirror-symmetrical manner to achieve good isolation. The 1 mm wide opening divides the L-slot structure into a longer open-slot and a shorter open-slot, and two different feed monopoles are designed to couple and excite the resonance modes of the slot by switching between the two different feed monopoles to cover LTE700/GSM850/900 and GSM1800/1900/UMTS/LTE2300/2500, respectively. The measured isolation is better than 11 dB, the measured antenna efficiency is better than 40%, and the calculated ECCs from measured radiation patterns are lower than 0.3.

KEYWORDS:

• Open-slot antennas
• multi-input multi-output (MIMO) antennas
• mobile antennas
• LTE antennas
• reconfigurable antennas
• smartphone antennas

Disclosure statement

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

Additional information

Funding

This work was supported by the Ministry of Science and Technology, Taiwan: [Grant number MOST 107-2221-E-606-004-].

Notes on contributors

Shu-Chuan Chen

Shu-Chuan Chen received the B.S. and M.S. degrees in electrical engineering from the Chung Cheng Institute of Technology, National Defense University (CCIT, NDU), Taoyuan, Taiwan, in 1998 and 2004, respectively, and the Ph.D. degree in electrical engineering from National Sun Yat-sen University, Kaohsiung, Taiwan, in 2012. Since 2012, she has been an Assistant Professor with the Department of Electrical and Electronic Engineering, CCIT, NDU, where she became an Associate Professor and Professor in 2016 and 2019, respectively. She holds over 20 patents, including USA, Taiwan, and Chinese patents. Her current research interests include internal antennas for mobile communication devices.

Sheng-Min Li

Sheng-Min Li received the B.S. degrees in electrical engineering from the Chung Cheng Institute of Technology, National Defense University (CCIT, NDU), Taoyuan, Taiwan, in 2016, and is currently pursuing the M.S degree in electrical engineering from the Chung Cheng Institute of Technology, National Defense University (CCIT, NDU), Taoyuan, Taiwan. His main research interests are in internal antennas for mobile communication devices. His current research interests include antenna and microwave circuit design.