Design of a smartwatch antenna for 5G

Abstract

It is widely acknowledged that the size of the smartwatch is very limited, which leads to difficulty when working on designing a smartwatch antenna. Moreover, the design is more arduous when dealing with multi-band and small antennas. As a result, this project will focus on finding a method to design a smartwatch antenna to tackle such problems based on the theory of characteristic modes (TCM). It is possible for an antenna to cover a multi-band by the usage of the theory. In this project, five desired bands are covered, namely 5-GHz WLAN (5725-5875 MHz), 4.9-GHz 5G (4800-5000 MHz), 3.5-GHz 5G (3400-3600 MHz), WLAN/Bluetooth 2.4-GHz (2400-2480 MHz), and GPS L1 (1575 MHz). With the screen as a part of the chassis, there are two sections required which have a total length of 125 mm and they occupy 77% of the smartwatch bodys perimeter. In addition, the whole antenna design includes the smartwatch's screen, which is treated as a component. Moreover, the antenna can be used on different sizes of grounds. In terms of the flexible printed circuit (FPC), which is used to build the connection between the system PCB and the screen, its position is also changeable according to different designs. The usage of the TCM theory can achieve a multi-band smartwatch antenna while minimizing the size and ground of the antenna with the use of the full screen of the smartwatch.