天線工程期中報告 “Low-SAR Hexa-Band Antenna for Mobile 論文研討: Guo Liu*, Chiara Pelletti*, and Raj Mittra “Low-SAR Hexa-Band Antenna for Mobile Applications,” Antennas and Propagation & USNC/URSI National Radio Science Meeting, 2015 IEEE International Symposium on., pp. 372-373, July. 2015. 報告人: 碩研通訊一甲 MA433102 林榮達 Southern Taiwan University of Science and Technology
Outline 1.摘要 2.天線架構 3.結果與討論 4.結論 5.心得 6.參考文獻
摘要 此篇論文主要是在探討如何在一個有金屬背 面的六頻手機天線上運用簡單的結構來降低 此篇論文主要是在探討如何在一個有金屬背 面的六頻手機天線上運用簡單的結構來降低 其SAR值,該天線應用的頻帶為LTE Band 13 (747-787 MHz); DCS1800 (1710-1880MHz); PCS1900 (1850-1990MHz); WCDMA(1920-2170MHz); LTE Band 40 (2300-2400 MHz);Band 41(2496-2690MHz),且其所設計的架構只佔電路板上19 ×29.5平方毫米的一小塊面積而已 SAR(Specific Absorption Rate)值為輻射吸收率,用來表示輻射對人體的影響,其中腦部的SAR值必須小於1.67瓦特才算安全
天線架構 Coupling strip(耦合路徑)是為了增加高頻的頻寬而9 nH的片式電感器是為了讓天線在低頻有良好的阻抗匹配
結果與討論(1) S11 of the proposed hexa-band antenna with and without head model
結果與討論(2) ANTENNA PERFORMANCE IN THE PRESENCE OF THE HEAD MODEL, WITH AND WITHOUT METAL BACKING
結果與討論(3) SAR distribution at 770 MHz, 1.75 GHz, 1.9 GHz, 2.1 GHz, 2.35 GHz and 2.5 GHz.
結論 在本文中,作者優化了六頻的手機天線設計, 不只是用一個9nH的片狀電感來使應用頻寬更為寬廣,更有效應用金屬背面來降低SAR值以符合IEEE的標準要求,作者也將繼續研究是否 可以改變金屬背面的位置,讓沒有接近頭部所模擬的SAR值跟接近頭部所模擬的SAR值更為相近。
心得 本文的天線設計架構簡單、更重要的是雖然 現在能夠做出應用6個頻帶的手機天線很多, 但要像作者這樣用簡單的架構就能有效的降低輻射對於人體影響的天線卻很少,這讓我發現到即便能做出應用頻帶很多的天線出來 ,要是不去考慮輻射對於人體的影響的話, 還是很難被大眾所使用的。
參考文獻 [1] Cho-Kang Hsu and Shyh-Jong Chung, “Compact antenna with U-shaped open-end slot structure for multi-band handset applications,” IEEE Transactions on Antenna and Propagation, vol 62, no. 2, pp. 929-932, Nov. 2013. [2] Jui-Han Lu, and Jia-Ling Guo, “Small-size octaband monopole antenna in an LTE/WWAN mobile phone,” IEEE Antennas and Wireless Propagation Letters, vol. 13, pp. 548–551, Mar. 2014. [3] Zheyu Wang, Lanlin Z. Lee, Dimitris Psychoudakis, and John L. Volakis, “Embroidered multiband body- worn antenna for GSM/PCS/WLAN communications,” IEEE Transactions on Antenna and Propagation, vol 62, no. 6, pp. 3321-3329, Jun. 2014. [4] Yong-Ling Ban, Yun-Fei Qiang, Zhi Chen, Kai Kang, and Joshua Le- Wei Li, “Low-profile narrow-frame antenna for seven-band WWAN/LTE smartphone applications,” IEEE Antennas and Wireless Propagation Letters, vol. 13, pp. 463–466, Mar. 2014. [5] IEEE Standard for Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3KHz to 300GHz, IEEE Std C95.1-1991, Institute of Electrical and Electronics Engineers, Inc