天線期中報告 Southern Taiwan University Department of Electronic Engineering Compact Internal Wideband Antenna for Wireless USB Dongle Application 論文作者： Jin-Gang Gong, Yong-Chang Jiao, Qiao Li, Yue Song, and Jian Wang 報告人 : 碩研電子一甲 MA 許勝貿

摘要 A compact internal wideband antenna suitable for integration with the printed circuit board (PCB) of a wireless universal serial bus (WUSB) dongle is presented. The proposed antenna mainly comprises a folded metal plate with two sides beveled and a short-circuited pin connected to the system ground plane. Within the short-circuited pin, the impedance bandwidth improved from 53% to about 136%, and a large measured operational bandwidth from 2.3 to 10.8 GHz is obtained, which easily covers the Wibro, WLAN, WiMAX, S-DMB, and UWB frequency bands. The simple configuration and miniaturized geometry of 5X12.5X16 mm 3, the proposed antenna is easy to be fabricated by bending a sample metal plate. 1 Jin-Gang Gong, Yong-Chang Jiao, Qiao Li, Yue Song, and Jian Wang

天線設計 2 Fig. 1. (a) Configuration of the proposed internal antenna mounted on the PCB of a wireless USB dongle. (b) Detailed dimensions of the unfolded internal antenna. (c) Top view of the proposed antenna. Jin-Gang Gong, Yong-Chang Jiao, Qiao Li, Yue Song, and Jian Wang

3 Fig. 2. Effect of the short-circuited pin on the impedance matching characteristic. 此模擬結果中可看出， 接上短路腳後，頻寬由原 本的 53% (5.0~8.6 GHz) 提高到 136% (2.1~11 GHz) Jin-Gang Gong, Yong-Chang Jiao, Qiao Li, Yue Song, and Jian Wang

4 Fig. 3. Photograph of the manufactured internal antenna. (a) Top view. (b) Bottom view. Jin-Gang Gong, Yong-Chang Jiao, Qiao Li, Yue Song, and Jian Wang

5 實驗結果與討論 Fig. 4. Simulated and measured VSWRs of the proposed internal wideband antenna. 由此圖可看出 VSWR 的 模擬 結 果跟測量結果差 異並不是很大， 還在我們可以接 受的範圍 Jin-Gang Gong, Yong-Chang Jiao, Qiao Li, Yue Song, and Jian Wang

6 Fig. 5. Proposed antenna attached to a laptop in two situations. (a) Case 1: Proposed antenna is attached vertically to the laptop. (b) Case 2: Proposed antenna is attached horizontally to the laptop. Jin-Gang Gong, Yong-Chang Jiao, Qiao Li, Yue Song, and Jian Wang

Fig. 6. Simulated and measured radiation patterns: (a) 2.4 GHz (b) 5 GHz (c) 8 GHz. 7 在 x-y plane 輻射圖 案幾乎是全方位的 Jin-Gang Gong, Yong-Chang Jiao, Qiao Li, Yue Song, and Jian Wang

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9 Fig. 7. Measured peak antenna gain. 在整個工作頻 帶從 2.1 到 4.6 dBi 做天線增 益的變化 Jin-Gang Gong, Yong-Chang Jiao, Qiao Li, Yue Song, and Jian Wang

10 Fig. 8. VSWR characteristic for various length Ls. 在 6-8 mm 頻帶性能大 大提升，但是到了 9mm 的時候在較高頻 的情況下發生了阻抗 不匹配的問題 為了實現良好的阻抗 匹配，應控制好短路 腳的位置 Jin-Gang Gong, Yong-Chang Jiao, Qiao Li, Yue Song, and Jian Wang

11 參數特性研究 Fig. 9. VSWR characteristic for various length L 1. Jin-Gang Gong, Yong-Chang Jiao, Qiao Li, Yue Song, and Jian Wang

12 Fig. 10. VSWR characteristic for various length L 3. Jin-Gang Gong, Yong-Chang Jiao, Qiao Li, Yue Song, and Jian Wang

13 Fig. 11. VSWR characteristic for various length α. Jin-Gang Gong, Yong-Chang Jiao, Qiao Li, Yue Song, and Jian Wang

14 結論 The antenna is easily fabricated by bending a metal plate with two sides beveled. By introducing a short-circuited pin connected to the system ground plane, the antenna shows a very wide impedance bandwidth of approximately 8.5 GHz (2.3–10.8 GHz), covering the 2.4-GHz WLAN, Wibro, WiMAX, S- DMB, and UWB system bands. The radiation patterns and the antenna gain are measured, and a parametric study is carried out. The effects of a laptop on the radiation characteristics are discussed. The proposed antenna can be embedded in a USB dongle easily due to its compact size and low-profile characteristics. Jin-Gang Gong, Yong-Chang Jiao, Qiao Li, Yue Song, and Jian Wang

心得 15 透過即插即用的功能，傳統的 USB 可以用於大多數數位產品之間 的資料交換。但因為 USB 有傳輸線的存在，導致在移動中的環境 有使用上的困擾。 隨著 WUSB 的發展可以讓數位產品之間的資料交換不會因為傳輸 線的存在而受到種種的限制。 只要能克服設計上所遇到的艱難問題，相信 WUSB 一定能在現今 的社會裡普及化。