研究生(外文):CHIA-HAO WU
論文名稱:應用於智能手錶穿戴式天線之設計
論文名稱(外文):Design of Wearable Antenna for Smart watch Applications
指導教授:孫卓勳
學位類別:博士
校院名稱:國立臺北科技大學
系所名稱:電子工程系
論文出版年:2018
語文別:英文
論文頁數:73
論文摘要
本論文為物聯網應用提供了智能手錶中穿戴式之天線,提出了用於可穿戴設備的天線設計概念,利用共面波導短路至背面的接地,天線設計為0.4 mm厚的FR4,尺寸為20 mm×15 mm,實測天線的反射係數時,天線含有人體手腕的實測頻寬為237 MHz(2.38-2.62 GHz;約9%),天線不含人體手腕的實測頻寬為300 MHz(2.33-2.63 GHz;約12%),無論是否含手腕都可以用於2.4 GHz藍牙/ WiFi頻帶,但近年對於連上網路的速度需求越來越大,多天線設計可增進資料量傳輸速率的提昇,因此針對智能手錶的WiFi 802.11ac頻段(5.2-5.84 GHz)設計MIMO天線,此天線採用聚酰胺基材製造,嵌入智能手錶模型的錶帶中;而模型是使用塑料材料的三維蝕刻製成的,先設計二個單極(two-element MIMO)天線,於結構中加入stub和notched設計探討天線隔離度,再設計四個單極多進多出(four-element MIMO)天線,此天線結構簡單,並與智能手錶的系統接地連接,天線的包絡相關係數在工作頻帶中顯著低於0.005。另外,本研究結果顯示其與人體手腕的測量數據於-6 dB阻抗頻寬為5.2-5.84 GHz,符合WiFi 802.11ac範圍,此天線量測之效率為93%-97%,而結合假手量測之效率為45%-55%。
論文外文摘要
This study presents a wearable antenna on the wrist for IoT application. An antenna design concept for a wearable device is proposed wherein one coplanar waveguide is ground-connected to short the bottom patch. The printed antenna is fabricated on 0.4-mm-thick 20 mm × 15 mm FR4 substrate. The measured bandwidth of the printed antenna with and without human’s wrist exhibited 237 MHz (2.38–2.62 GHz; approximately 9%) and 300 MHz (2.33–2.63 GHz; approximately 12%), which is sufficient for 2.4-GHz Bluetooth/WiFi band.
In order that, the wireless WiFi access points use the multiple input–multiple output (MIMO) multiantenna to achieve a high transmission speed, and the WiFi 802.11ac (5.2–5.8 GHz) standard supports an 8 × 8 antenna, which substantially increases the transmission speed. In second part, a compact two-element MIMO antenna design operating within the WiFi 802.11ac bands (5.2–5.84 GHz) for a smart watch. The antenna is fabricated using a polyamide substrate and embedded into the strap of a smart watch model; the strap is created using three-dimensional etching of plastic materials.
Then the four-element MIMO antenna is designed from two-element MIMO antenna, and is connected to the system ground plane of the smart watch. Due to the stub and notched block between two antennas and the slit in the system ground, the four-element MIMO antenna exhibits favorable isolation. Moreover, the envelope correlation coefficient of the antennas is considerably lower than 0.005 in the operating band. The measured −6-dB impedance bandwidths of the four-element MIMO antenna with the human wrist encompass the WiFi 802.11ac range of 5.2–5.84 GHz; moreover, an isolation of more than 20 dB is achieved. The measured antenna efficiency with and without a phantom hand are 45%–55% and 93%–97%, respectively.