TCM-based Low-SAR Antenna for Smartwatch Applications

In this paper, a three-band low specific absorption rate(SAR) smart watch antenna is designed. Firstly, the characteristic modes of the composite structure of the antenna and the lossy dielectric are calculated, and the low-SAR characteristics of the antenna are realized by exciting the low-coupling mode of the antenna in the Bluetooth band and the 3.5 GHz band. The -6dB bandwidth of the antenna can effectively cover 1565MHz-1585MHz, 2400MHz-2485MHz and 3400GHz-3600GHz. The total efficiency of the antenna in free space in all three frequency bands is greater than 80%. The 10g Body SAR of the antenna at 2440MHz is 1.05W/Kg, and the 10g Body SAR at 3500MHz is 1.3W/Kg.