由於通訊科技的發展相當地蓬勃快速，高效能的通訊系統與元件的設計與開發可以讓我們更有效率地使用有限的頻譜資源。而在通訊系統中，濾波器是最重要的元件之一。本研究的主要目的在於實現高性能濾波器設計，所以選擇合成elliptic function的頻率響應特性。在微波濾波器的實現上，我們以Brune section來達到我們所要的目標。

首先，我們研究了Saito以及Rhodes等人所提出來之Brune section實現方法的優缺點，因此提出了我們近似的Brune section。然後進行濾波器輸出入點之阻抗匹配，以達到濾波器通帶接近equal ripple的頻率響應特性。最後，實際製作濾波器、經過量測、並與模擬比較，證明了我們提出的電路為可行之方法。

Due to the rapid development of communication technologies, the study and design of high performance systems and components help us share the limited frequency spectrum more effectively. Microwave filter design is one of the most important key technologies. The purpose of this search is to design high performance filters with elliptic function response. Brune section is selected to achieve this goal. Therefore, the main work of the research is to find a circuit realization of Brune section which is exact and easy to fabricate.

First, we studied the equivalent circuits of Brune section proposed by Saito and Rhodes. Based on this, we propose our approximated Brune section. Then we match the input and output impedances of a filter with this Brune section for an equal-ripple frequency response in the pass-band. Several circuits are fabricated. After the measurement and comparison with the simulated data, we have justified our method.

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