本文選題：L波段　切入點：脈沖功率放大器　出處：《電子科技大學》2015年碩士論文

【摘要】：脈沖功率放大器廣泛應用于雷達和無線通信發(fā)射機中,是發(fā)射機的核心部件,其性能的好壞直接決定整個通信系統(tǒng)的性能。相對于真空器件,固態(tài)器件具有結構緊湊、可靠性好、工作電壓低等優(yōu)點。因而固態(tài)脈沖功率放大器的研究成為熱點。本文將要完成L波段固態(tài)脈沖功率放大器的設計。經(jīng)過分析和比較,選擇了功放加脈沖調制電路的架構。整個放大器由預驅動級、驅動級和功放級三級構成。本文首先介紹了功放的分類,根據(jù)不同類型功放的特點,選擇預驅動級和驅動級工作于A類,功放級工作于AB類。然后使用ADS軟件,采用小信號S參數(shù)法仿真了各級放大器的穩(wěn)定性因子,確保放大器穩(wěn)定地工作,設計了預驅動級和驅動級的輸入輸出匹配電路和直流偏置電路;以負載牽引的方法仿真設計了功放的輸入輸出匹配電路,使放大器的輸出功率和增益達到設計要求。通過ADS軟件對功放的版圖進行了Momentum電磁仿真,使仿真結果與實際情況更接近。文中對比介紹了開關調制、柵極調制、漏極調制等不同調制方式的特點,最終選擇了漏極調制方式。使用具有快速上升沿和下降沿的功率MOSFET驅動晶體管的漏極實現(xiàn)脈沖調制。本文為功率放大級設計了溫度補償電路,可以將溫度對功放靜態(tài)工作點的影響降到最低。最后使用Protel99軟件設計了電源和調制電路的PCB版圖,使用AutoCAD軟件設計了射頻放大鏈路的電路版圖和金屬屏蔽結構件。完成了功放和調制電路的設計仿真,需要對電路進行測試。本文介紹了調試過程中需要注意的問題,并為不同的電路模塊和脈沖功放整機設計了不同的調試方案。主要使用矢量網(wǎng)絡分析儀、信號源、功率計、衰減器等測試儀器對電路進行了調試,最后測得驅動放大器在工作頻帶內的增益為31dB,功率放大級的增益為20dB,脈沖輸出功率達到250W,工作頻帶內增益平坦度小于1dB。脈沖上升沿為35ns,下降沿46ns,脈沖頂降小于0.81dB,達到了設計指標。最后對全文進行了總結,得出了相關結論,指出了文中存在的不足,并提出了相應的改進方向。
[Abstract]:Pulse power amplifier is widely used in radar and wireless communication transmitter. It is the core component of transmitter. Its performance directly determines the performance of the whole communication system. Therefore, the research of solid-state pulse power amplifier has become a hot topic. This paper will complete the design of L-band solid-state pulse power amplifier. The structure of amplifier plus pulse modulation circuit is selected. The amplifier consists of three stages: predrive stage, drive stage and power amplifier stage. This paper first introduces the classification of power amplifier, according to the characteristics of different types of power amplifier. The predrive stage and drive stage are selected to work in Class A and the power amplifier stage works in Class AB. Then the stability factor of the amplifier is simulated by using the small signal S parameter method with ADS software to ensure the stable operation of the amplifier. The input and output matching circuit and DC bias circuit of the predrive stage and the drive stage are designed, and the input and output matching circuit of the power amplifier is simulated by the method of load traction. The output power and gain of the amplifier meet the design requirements. The Momentum electromagnetic simulation of the power amplifier layout is carried out by ADS software, which makes the simulation results closer to the actual situation. The switching modulation and gate modulation are compared and introduced in this paper. The characteristics of different modulation modes, such as drain modulation, are finally selected. The pulse modulation is realized by using a power MOSFET driving transistor with fast rise edge and drop edge. A temperature compensation circuit is designed for the power amplifier stage. The influence of temperature on the static working point of power amplifier can be minimized. Finally, the PCB layout of power supply and modulation circuit is designed by using Protel99 software. The circuit layout and metal shielding structure of RF amplifier link are designed by using AutoCAD software. The design and simulation of power amplifier and modulation circuit are completed, and the circuit needs to be tested. Different debugging schemes are designed for different circuit modules and pulse power amplifier. The circuit is debugged by using vector network analyzer, signal source, power meter, attenuator, etc. Finally, the gain of the driving amplifier in the working band is 31 dB, the gain of the power amplifier is 20 dB, the output power of the pulse is 250 W, the gain flatness in the working band is less than 1 dB, the rising edge of the pulse is 35 ns, the descending edge is 46 ns, and the top drop of the pulse is less than 0.81dB. Finally, the paper summarizes the whole paper. The conclusion is drawn, the deficiency of the paper is pointed out, and the corresponding improvement direction is put forward.
【學位授予單位】：電子科技大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：TN722.75

【參考文獻】

相關碩士學位論文 前1條

1 黃謀輝;射頻功率放大器的研究與設計[D];北京郵電大學;2007年

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本文編號：1653707