volume | PIER Journals

Abstract

This paper introduces a wearable quad-band-notched two-port Multiple Input Multiple Output (MIMO) antenna with coplanar waveguide (CPW)-fed for 5G applications. The antenna uses a liquid crystal polymer (LCP) flexible substrate with dimensions of 30 mm * 54 mm * 0.1 mm. The proposed antenna achieves four notched bands by etching four C-shaped slots on the patch and introduces a fence structure in the middle to enhance the isolation between the antenna elements, which ultimately achieves a band coverage of 3.26-10.8 GHz, with the notched-band coverage of 4.0-4.57 GHz (C-band radar Note7), 4.8-5.0 GHz (N79 mobile), 5.62-6.0 GHz ( WLAN downlink), and 8.08-8.79 GHz (ITU-R), peak gain of 6.9 dBi, radiation efficiency of above 70%, and isolation greater than 20 dB. In addition, the important performance parameters of the designed MIMO antenna include envelope correlation coefficient (ECC), diversity gain (DG), channel capacity loss (CCL) and total active reflection coefficient (TARC). The antenna is subjected to bending and human body experiments, and all the results show that the antenna has the advantages of small size, multiple notched bands, and high isolation, which has a good prospect of application in the field of wearable antennas for the Internet of Things (IoT).

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Dr. Jiali Wang

Professor Chengzhu Du

Dr. Jun Chu

Dr. Ruomeng Li