適用在雙頻/寬頻功率分配器之設計

Design of Power Dividers for Dual/Wide Band Application

謝章群(Zhang-Qu Hsieh)

指導教授 ： 湯敬文

國立中正大學/工學院/電機工程學系/碩士(2014年)

摘要

摘要
本論文分兩部分，第一部分為雙頻功率分配器，第二部分為三線耦合寬頻等功率分配器。
第一部分為第三章的雙頻Gysel功率分配器，由二個Schiffman相移器串聯取代傳輸線，得到雙頻效果。改良Gysel功率分配器，可調整奇偶模阻抗得到想要的頻帶。此外藉由調整傳輸線輸線阻抗，可獲得欲設計之任意功率比，設計出雙頻不等功率分配器，頻帶位置比和功率比皆可由數學公式推導並設計。
第二部分為第四章的寬頻等功率Wilkinson功率分配器，利用三線耦合在輸入端作補償的方法，可在頻帶內產生額外兩個極點，進而增加頻寬，設計出-15dB比例頻寬為81.8%功率分配器，並且頻帶內擁有良好隔離度。
上述電路均使用全波電磁模擬軟體模擬，並實際製作。經由測量結果與理論分析和電磁模擬相比，證實有良好一致性。

關鍵詞-雙頻不等功率分配器、寬頻帶等功率分配器、三線耦合。

關鍵字

寬頻帶等功率分配器 ； 雙頻不等功率分配器 ； 三線耦合

並列摘要

Abstract
This thesis is included two parts: the first part is a dual-band power divider and the second part is about three-coupled-line broadband equal power divider.
The first part shown in chapter 3 is the dual-band power divider. In order to improve the traditional Gysel power divider, the 180 transmission line connected with two output ports are replaced two series-connected Schiffman phase shifters, thus the dual-band response can be obtaianed. Moreover, the even- and odd-mode impedances of the coupled line can be modified to fit the interested frequency bands. Furthermore, arbitrarily power ratio can achieve by change of four transmission lines’ impedances to get unequal power division of dual passbands. In addition, the analytical equations are derived for the frequency ratio and power ratio.
The second part shown in chapter 4 is the broadband equal power divider with three coupled lines. At input port, two additional poles within the passband can be obtained by using three-coupled-lines compensated circuit, which can to improve the passband’s bandwidth. The bandwidth of 81.8% is designed for power divider with |S11| < -15dB. This power divider is also provide good isolation.
All the circuits are simulated with full-wave electromagnetic simulator and implement. The results are well match between electromagnetic simulations and measurements, which can evidence the availability of all proposed circuits.

Keywords: dual-band unequal power divider, broadband equal power divider, three- couple-line.

並列關鍵字

broadband equal power divider ； dual-band unequal power divider ； three- couple-line

參考文獻

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