對於Gysel功率分配器相關文獻，大部分使用奇偶模態分析方式，只針對中心頻率點設計，或以最佳化方法求得電路架構應有的響應結果。本論文提出不同的角度設計方式，整合大部分功率分配器之相關應用，藉由找出其等效電路，運用合成方式如此不但符合設計需求，也可掌握此電路架構物理特性。一開始先以近似設計原始二路Gysel功率分配器，再推廣到不等功率輸出設計。

然而我們以奇偶模態分析原始電路時，發現兩模態的等效電路不會一樣，以致於在設計頻帶內無法有良好之隔離度響應，所以大部分文獻只能在中心頻率點上設計分析。因此我們引進一個理想的1:-1變壓器，並增加冗餘元件改變原始電路，選擇讓奇偶模態等效電路相同條件下，使其合成出同樣的響應函數，讓頻帶內的隔離度變好，進而提出對邊短路耦合線功率分配器。之後用上述改良的條件為基準，應用到相關設計Gysel功率分配器之電路，同時也討論對於180o相位移在匹配端或隔離端功率分配器之架構分類。

在設計改良的Gysel功率分配器當中，Gysel電路頻寬有其限制範圍，本論文提出解決方式，並延伸到高階Gysel功率分配器，設計成擁有超寬頻響應特性。針對現今電子產品主要以縮小面積為訴求，本論文提出微型化功率分配器，以期符合趨勢所需，最後探討至N路Gysel功率分配器的設計方式。而實作部分我們以原始Gysel電路與改良的功率分配器比較結果，來驗證其合成方式之可行性。

So far, most of the papers about Gysel power divider are analyzed by even-mode and odd-mode method at center frequency, or by numerical optimization. In this thesis, we propose a different way to design all the related power divider based on synthesis methods. This not only depend on specification to design but know the possibility for the circuit. First at all, we use synthesis theories to design original Gysel power divider, and then extend unequal power divider.
We analyze original Gysel power divider by even-mode and odd-mode and find the different equivalent circuits in even-odd mode. This reason will cause weak isolation, so most papers are only designed at center frequency no broadband bandwidth. We introduce ideal 1:-1 transformer and add redundant elements to get the same equivalent circuit. Therefore, we propose modified diagonally short-circuited coupled line power divider, it can be synthesized the same response so that isolation would be improved in the passband. Furthermore, we apply above modified condition and then extend related papers research. At the same time, the 180o phase shift can be designed into the matching or the isolation network power dividers.
When designing the modified Gysel power divider, the bandwidth has limitation. We propose the solution and even develop higher order Gysel power divider to own ultra wideband response. Nowadays, almost all electronic products become size reduction, so this thesis also proposes miniaturized power divider. Finally, we also discuss how to design N-way Gysel power divider. We compare diagonally short-circuited coupled line power divider with original Gysel power divider and validate the synthesis method by electromagnetic simulations and experiments.

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[3.17] A. M. Abbosh, “Multilayer inphase power divider for UWB applications,” IEEE Microwave and Optical Tech. Lett., vol. 50, no. 5, pp. 1402-1405, May 2008.

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[3.20] B. L. Ooi, “Compact EBG in-phase hybrid-ring equal power divider,’’ IEEE Trans. Microwave Theory Tech., vol. 53, no. 7, pp. 2329-2334, Jul. 2005.

[3.21] J. Guan, L. J. Zhang, Z. Y. Sun, Y. Q. Leng, Y. T. Peng, and Y. P. Yan, “Modified Gysel power divider with harmonic supperssion performance,” Progress In Electromagnetics Research C, vol. 31, pp. 255-269, Aug. 2012.

[3.22] R. J. Wenzel, “Synthesis of combline and capacitively loaded interdigital bandpass filters of arbitrary bandwidth,” IEEE Trans. Microw. Theory Tech., vol. MTT-19, no. 8, pp. 678-686, Aug. 1971.

[5.1] H. R. Ahn, K Lee, and N. H. Myung, “General design equations of n-way arbitrary power dividers,” IEEE MTT-S Int. Microw. Symp. Dig., pp. 65-68, June 2004.