在本論文中，將探討利用智慧型超穎材料(Intelligent Metamaterial)來降低天線對人頭產生的特定吸收率(Specific Absorption Rate, SAR)。智慧型超穎材料能判斷是否靠近人頭而呈現不同特性，天線在沒有靠近人頭時，超穎材料不影響天線效能；但當天線靠近人頭時，超穎材料能降低SAR值。
本文將分別介紹利用阻抗不匹配以及頻帶移動兩種設計方式來設計兩種不同的智慧型超穎材料。前者具有寬頻的效果，SAR值最多可降低56.7%。後者尺寸較小，適用於手機通訊，抑制效果可達40%。兩者對於天線的場型都幾乎沒有影響。
最後，將智慧型超穎材料應用在手機天線上，智慧型超穎材料的尺寸僅40 mm × 20 mm × 0.8 mm，當天線沒有靠近人頭時不影響天線的效能，靠近人頭時可降低SAR值達41.7%。

In this thesis, intelligent metamaterial was designed to reduce the peak specific absorption rate (SAR) value. Intelligent metamaterial means that when the antenna is far away from a human head, the metamaterial behaves like air and it does not affect the antenna performance; when the antenna is close to a human head, however, the metamaterial acts like a single negative (SNG) material.
We designed two kinds of intelligent metamaterial structures. One makes use of impedance mismatching, and the other makes use of the frequency band shift property to reduce the peak SAR value at the operating frequency. The former structure is broadband, and it can reduce the peak SAR value by 56.7%. The latter structure has a much smaller size compared to the former one, and it is suitable for cellular phone applications. The peak SAR value can be reduced by 40% using the latter structure. The proposed two kinds of the intelligent metamaterial structures do not affect the antenna performance.
Finally, the intelligent metamaterial has been applied to a cellular phone. The dimension of the intelligent metamaterial is only 40 mm × 20 mm × 0.8 mm. The intelligent metamaterial does not affect the antenna performance when the antenna is far away from a human head. When the antenna is close to a human head, the peak SAR is reduced by 41.7%.

致謝 I
中文摘要 III
Abstract IV
目錄 V
圖表目錄 VII

第一章 序論 1
1-1 研究動機 1
1-2 國內、外技術比較 2
1-3 研究方法 2
1-4 論文大綱 3

第二章 超穎材料及SAR的簡介 4
2-1 超穎材料簡介 4
2-2 SAR簡介 7

第三章 利用阻抗不匹配設計智慧型超穎材料 9
3-1 單一晶胞(unit cell)分析 9
3-2 設計概念 12
3-3 超穎材料對SAR值的影響 15
3-4 超穎材料對天線的影響 18
3-5 具有寬頻效果的智慧型超穎材料 20
3-6 空氣間隙對SAR值的影響 23

第四章 利用頻帶移動設計縮小化智慧型超穎材料 27
4-1 設計概念 27
4-2 超穎材料對SAR值的影響 32
4-3 超穎材料對天線的影響 34
4-4 空氣間隙對SAR值的影響 37

第五章 手機天線結合縮小化智慧型超穎材料 48
5-1 PIFA手機天線設計 48
5-2 將智慧型超穎材料應用於手機天線 51
5-3 實作與量測 56

第六章 結論 60

參考文獻 61

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