A wearable CPW-fed quad-band-notched two-port MIMO antenna for IoT applications

This paper presents a wearable quad-band-notched two-port Multiple Input Multiple Output (MIMO) antenna and it utilizes coplanar waveguide (CPW) for feeding for wearable IoT applications. The antenna uses Liquid crystal polymer (LCP) flexible substrate with dimensions of 30mm*54mm*0.1mm. By creating four C-shaped slots on the patch, the proposed antenna creates four notched bands. To improve the isolation between the antenna elements, a fence construction is added in the center. The proposed antenna 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)`, and the isolation is greater than 20 dB. In addition, the key performance metrics of the MIMO antenna design, including ECC, DG, and TARC, and 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 wearable field.