本論文提出以奇偶模分析實現二元密置陣列之集總解耦合網路。此架構乃以奇偶模分析方法為基礎，使用產業界常用之集總元件實現解耦合網路，其系統化設計之參數關係可直接透過公式推導所獲得。因此，可在不需施作試誤法的情況之下完成設計，並能同時達到完美系統阻抗匹配與端埠隔離度，有效提升多重輸入多重輸出系統之傳輸效能。
該解耦合網路，在二元密置陣列天線饋入點處擺放集總元件電路佈局，並根據對稱型電路特性進行奇偶模分析。首先，從參數較少的偶模態進行設計，透過引入 L 型匹配網路達到奇模匹配，並決定其設計參數；接著，再進行奇模態分析，此時奇模半電路將為一π型匹配網路，並可透過剩餘設計參數完成奇模匹配的獨立設計。當奇偶模匹配同時都達成匹配時，此解耦合網路才能得到良好的系統阻抗匹配和高端埠隔離度。
本論文將首先詳細探討傳統並聯電抗元件實現解耦合之利弊及奇偶模法實現解耦合網路之分析。經整合後依序探討以奇偶模分析實現集總解耦合網路之電路佈局、設計原理、模擬與量測結果，並進行相關討論。經模擬和實驗的驗證，都能在二元密置陣列的解耦合要求下，實現良好的整體阻抗匹配，同時擁有優秀二元密置陣列的高端埠隔離度。最后，利用兩款二元密置陣列天線充分驗證此構想之可行性，其模擬與實驗結果十分吻合，可做為未來模組化設計之依據。

In this thesis, novel lumped decoupling networks for arbitrary two-element closely-spaced arrays are proposed and developed using even-odd-mode analysis. The framework takes the even-odd-mode analysis as the foundation and adopts frequently-used lumped elements to realize the decoupling network. The systematic design parameters can be deduced from equations directly. Therefore, the design can be accomplished without any trial-and-error method, but can still attain the perfect system resistance and port isolations matching, thus effectively improves the MIMO system transmission efficiency.
The lumped decoupling network is located at the antenna’s feed point and developed using even-odd-mode analysis due to its symmetry. On one hand, The analysis starts from the even mode which possesses relatively less design parameters, and the even-mode matching can be realized by introducing a L-section matching network. On the other hand, by utilizing the rest of design parameters in the π-section matching network, the odd-mode matching can be completed independently. As both even- and odd-mode matching is achieved, the two-element closely-spaced array can attain a superior overall impedance matching and high port isolation.
This thesis will first investigates both advantages and disadvantages of the conventional decoupling method using parallel reactive elements and another one developed based on the even-odd-mode analysis. Then, the circuit layout, design principles, and simulated and measured results of the lumped decoupling network are discussed in detail. As verified by the simulation and measurement, the lumped decoupling network can provide the two-element closely spaced array with good overall impedance matching and high port isolation at the same time. Finally, by utilizing two kinds of coupled array antennas to demonstrate the feasibility of the proposed concept, the agreement between the simulated and measured results is excellent. The topology of this design shows high potential to be a module design pattern to the industry.

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