A Cavity-Backed Annular Slot Antenna With High Efficiency for Smartwatches With Metallic Housing
| Autor: | Sing Wai Cheung, Di Wu |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Physics
Coaxial antenna business.industry Loop antenna 020208 electrical & electronic engineering Antenna measurement 020206 networking & telecommunications Slot antenna 02 engineering and technology Antenna factor Radiation pattern Antenna efficiency Optics 0202 electrical engineering electronic engineering information engineering Electrical and Electronic Engineering business Monopole antenna |
| Zdroj: | IEEE Transactions on Antennas and Propagation. 65:3756-3761 |
| ISSN: | 1558-2221 0018-926X |
| Popis: | A cavity-backed annular slot antenna designed for the use in smartwatches in the 2.4-GHz Wi-Fi band is proposed. The cavity is metallic and has a cylindrical shape with a volume of $\pi \times 21^{2}\times10$ mm3. An annular slot is cut along the edge of the top surface (as the smartwatch screen) of the cavity. The circumference of the annular slot is about $1\lambda$ , making the design small enough for the smartwatch applications. The resonant modes, current distribution, and transverse mode of the cavity-backed annular slot antenna are studied using simulations and the results are used to design a smartwatch antenna. The proposed smartwatch is studied in free space, on a computer hand model, and on a phantom hand using simulations and measurements. Measured results show that the antenna has an efficiency of 57%–66% on a phantom hand. To study the antenna in a more realistic environment, the electronic components inside the smartwatch are modeled as a metallic block. For health risk concerns related to exposure to an electromagnetic radiation, the specific absorption rate for the smartwatch in the wrist-worn and next-to-mouth conditions is also studied using simulations. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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