最近幾年無線通訊的使用者大量增加，這使得無線通訊服務的需求量直線上升，大量的需求也使得系統需要更大的涵蓋範圍、更多的容量、和更好的品質。而智慧型天線則是一種在無線通訊中能有效增進效能的技術。
切換波束型的智慧型天線系統在基地台上有固定數目的波瓣，基地台可選擇一個接收與發射性能較好也可降低干擾的波辦，來接收與發射對行動台的訊號。而使用動態切換波束天線系統的方法，可以建構出能調整扇形區域大小的智慧型扇形波束合成。透過這種改變可以達到負載平衡的效果，進而增加系統容量。
本論文在探討此種系統中引入一個波束構成方法，這是在1993年由M.H. Er所提出的，藉由可調整的主波瓣寬度以及降低平均旁波帶高度來製作陣列場型。我們在圓形天線上建立一組權重的資料庫，讓論文中所提出的智慧型天線可以在不均勻且高密度的使用者分布下可以調整出適當的扇形區域。模擬結果可驗證出所提出的技術可以有效改善傳統切換波束天線的效能。

Over the last few years‚ the number of subscribers of wireless services has increased at an explosive rate. This ever growing demand for wireless communications services is constantly increasing the need for better coverage‚ improved capacity and higher quality service. Smart antennas system is an effective technology for the performance improvement of wireless communications.
Switching-beam smart antennas use a number of fixed beams at an antenna site. The system provides a beam that offers the best signal enhancement and interference reduction. Using the approach of dynamic switching-beam antenna system‚ an intelligent sector beam synthesis of adjustable sector width can be established. By doing so‚ traffic load balancing can be achieved, and therefore, system capacity is increased.
In this thesis, a beam-pattern synthesis algorithm proposed by M.H. Er is applied to shape array patterns with an adjustable mainlobe width and average sidelobe level reduction. Using an established database of weighting for circular arrays, the proposed smart antennas can adjust suitable sectors for the high dense subscribers not uniformly distributed. Simulation results demonstrate the proposed technique can dramatically improve the performance of traditional switching-beam antennas.

感謝詞
中文摘要
英文摘要
目錄
圖表目錄
第一章 緒言
1.1 文獻探討
1.2 研究動機
第二章 智慧型天線與天線陣列訊號模型
2.1 智慧型天線技術
2.2 線性陣列訊號模式
2.3 圓性陣列訊號模式
第三章 陣列場型合成的最佳限制技術
3.1 問題描述
3.2方法
3.3 方法二
3.4 權重近似解
3.5 陣列場型模擬
3.6旁波帶特性
3.7 旁波帶相關模擬
第四章 具動態扇形波束合成之智慧型天線
4.1簡介動態扇形
4.2 實例探討
4.3系統架構
4.3.1 切換波束系統
4.3.2 結合演算法
4.4 彈性與容量
4.5 阻塞率模擬
4.6 錯誤率模擬
4.6.1 使用者角度分布
4.6.2 錯誤率
第五章 討論與建議
參考文獻

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