本論文針對2.4 GHz WLAN頻段，開發可支援MIMO技術的無線基地台多天線系統，本研究共提出兩個設計。第一部分是一個六天線系統，以槽孔天線與倒F天線作為單元天線，並使用集總元件縮小天線尺寸。該設計也藉由單元天線的擺放方式產生極化上的差別，以提高單元天線之間的隔離度。加入集總元件後的天線設計，雖犧牲了部分的天線輻射效率，但實測結果顯示，其輻射效率仍可維持在65~71%附近，尚有不錯的表現。為了測試天線的分集效果，也使用了一個有效分集增益量測系統量測實作的天線，驗證此天線系統具有良好的分集效果。
第二部分為一個八天線系統，以不同邊界條件與共振模態的槽孔天線作為單元天線，在六天線中的倒F天線為了減少和槽孔天線之間的耦合量，採用了垂直站立的倒F天線，使天線系統朝度增加。為了減少高度，八天線系統使用了兩種平面式的槽孔天線。除了運用集總元件，還利用了蜿蜒路徑縮小天線尺寸。將八支天線對稱放置在圓形平台上，可以達到場型分集與極化分集的效果，實測結果顯示八天線具有不錯的分集效果，可做為無線區域網路基地台天線使用。

This thesis focuses on the development of multi-antenna systems applicable to wireless local area network base stations. The thesis consists of two parts. The first part is a six-antenna system, which uses slot antenna and invert-F antenna as antenna elements. To achieve space diversity, antennas are miniaturized by adding lump elements. Moreover, by adjusting antenna orientations, it produces differences in polarization and hence improves the isolation between adjacent antennas. Though adding lump element may deteriorate antenna efficiency, the fabricated prototype still shows radiation efficiency between 65 to 71% and is acceptable for projected uses. To test the diversity performance, an effective diversity gain measured systemis used to verify the good performance of the fabricated prototype in antenna diversity.
The second part is an eight-antenna system. Two kinds of slot antennas are used as element antennas. The overall antenna system has a low-profile. To enhance the isolation among antennas, meandered slot are used to reduce antenna sizes. The eight antennas are arranged in a symmetrical fashion. Through the implementation and measurements, the fabricated prototype shows good performance in diversity. The antenna is suitable for WLAN base stations.

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