應用功率結合變壓器之達靈頓功率放大器與X頻段pHEMT製程功率放大器研製

Implementation on Darlington Power Amplifier Using Power Combining Transformer and X-band pHEMT Process Power amplifier

林喬盛(Qiao-Sheng Lin)

指導教授 ： 邱煥凱

國立中央大學/資訊電機學院/電機工程學系/博士(2012年)

摘要

本論文利用TSMC 0.18-μm CMOS製程以及WIN 0.15 pHEMT製程設計功率放大器(Power Amplifier, PA)，在設計上分成兩個部份，第一部分為使用功率結合技術，設計K頻帶至Ka頻帶達靈頓功率放大器。設計方面，以達靈頓架構將單顆電晶體之單增益頻率(frequency of unity current gain, fT)成倍頻延伸，並且透過fT的改變，最大可用增益(Maximum available gain, MAG)以及最大振盪頻率(Maximum fequency of oscillation, fmax)均會有所不同。接著對達靈頓架構做模擬以及小訊號分析，以找到主要關鍵點，功率結合技術方面，利用上下堆疊式變壓器將兩路差動達靈頓功率放大器做功率結合以提高輸出功率，實作方面，量測特性如下：增益量測在28.8 GHz有最大值，為6.1 dB，輸入回返損耗為25 dB，輸出回返損耗最高為20 dB，在28 GHz的 1-dB增益壓縮點輸出功率為12 dBm，飽和輸出功率為14 dBm，最高效率為1.5%。
第二部分為全積體化pHEMT功率放大器，應用頻率為X頻帶。設計方面，可分為兩級，分別為功率級以及驅動級，驅動級目的在於提高增益，功率級則在提供輸出功率。實作方面，電路在10 GHz時的量測特性如下：增益量測為24.3 dB，輸入迴返損耗為15.8 dB，輸出回返損耗為8.7 dB，1-dB增益壓縮點輸出功率為17.6 dBm，飽和輸出功率為20.8 dBm，最高效率為35.7%。

關鍵字

變壓器 ； 功率放大器 ； 達靈頓

並列摘要

This thesis presents power amplifier implemented in TSMC 0.18μm CMOS technology and WIN 0.15μm pHEMT technology. The implemented circuits include two PA categories. The first category is the design of K-band to Ka-band darlington power amplifier using power combining technology. In this design, we use darlington structure to entend the fT and the MAG as well as fmax change with fT. And then we analyze the darlington structure and simulate this structure to find the dominant factor. In power combining technology, we use the stacked coupling transformer to combine the output power of differential darlington power amplifier. And the measured results of this circuit are summarized as below: maximum power gain of 6.1 dB at 28.8 GHz, input return loss of 25 dB, output return loss of 20 dB. At 28 GHz the output power of 1-dB compression point is 12 dBm, saturated output power is 14 dBm and maximum PAE is 1.5%
The second category is the fully integrated pHEMT power amplifier in X-band. In this design, we divide this circuit into two parts. One part is drive stage, and it can enhance the power gain.The other part is power stage, and it can provide the output power. And the measured results of this circuit are summarized as below, power gain of 24.3 dB, input return loss of 15.8 dB, output return loss of 8.7 dB ,the output power of 1-dB compression point is 17.6 dBm, saturate power is 20.8 dBm and maximum PAE is 35.7%.

並列關鍵字

transformer ； Darlington ； Power amplifier

參考文獻

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