220GHz同轴谐振腔回旋管研究

同轴谐振腔相比波导谐振腔具有更大的功率容积,通过调整内外径的尺寸还可降低模式竞争。本文介绍了电子科技大学目前220 GHz同轴谐振腔回旋管的设计与研制工作,给出了谐振腔、电子光学系统与输出结构的设计参数与仿真结果,仿真结果表明该设计可获得100 kW以上的输出功率与20%以上的互作用效率。     

基于富铟团簇量子结构的双波长可调谐半导体激光器

本研究提出了一种采用增益芯片和光栅外腔的双波长可调谐半导体激光器。增益芯片采用了富铟团簇量子限制结构作为其量子限制结构,由于该结构独特的平顶增益特性,可以使激光器在双波长调谐范围内实现光强稳定。本研究中的谐振腔包括内部谐振腔和外部谐振腔,其中内部谐振腔由增益芯片的两个自然解理面构成,以支撑整个系统工作在特定波长。外部谐振腔由增益芯片的一个自然解理面和光栅构成,可实现969.1~977.9 nm的工作波长范围。最终该系统基于单个增益芯片和单个光栅实现了同步双波长输出,双波长的频率差在THz范围。本研究有望为实现双波长差频太赫兹源提供一种可能的解决方案。     

角锥棱镜阵列谐振腔输出模式研究

为了研究角锥棱镜阵列谐振腔的输出特性,利用角锥棱镜阵列作为后腔镜,与平面镜构成角锥棱镜阵列谐振腔,模拟计算了角锥棱镜阵列谐振腔输出模式的近场及远场分布,理论分析了谐振腔的相干输出,实验获得了采用该腔型的钕玻璃激光器的输出模式的近场及远场分布.结果表明,模拟计算与实验得到的模式分布相吻合,近场光斑外形为六边形,与角锥棱镜...     

基于单端开路系统函数的介质振荡器的设计

介绍了X波段的介质谐振腔稳频的振荡电路的理论分析和数值仿真设计.振荡器由高介电常数的介质谐振腔形成的反馈回路和单端开路负阻振荡器构成.谐振腔的设计可以用一个简单的传输线型的模型进行仿真,使得理论分析得以试验的证实.电路的仿真结果和测试结果吻合良好,其工作在10.576GHz,输出功率在16dBm,这种振荡器可以应用在很多微波系统.     

S波段5MW大功率速调管的研制

本文介绍了S波段脉冲5 MW高平均功率脉冲速调管的设计和制造情况。设计主要包括电子枪光学系统、电磁聚焦系统、高频谐振腔系统、射频馈入与输出系统、收集极热状态情况。研制的样管经测试已基本达到预期目标,研制过程中对部分关键工艺进行了研究,提高了速调管在大功率下的工作稳定性。     

高功率脉冲微波系统的研制

介绍了高功率脉冲微波系统的工作机理及应用,提出了采用刚管高压脉冲调制器作为激励源技术,利用脉冲磁控管输出高功率脉冲微波以及谐振腔体处理物料的设计思路。详细阐述了高压脉冲调制器、微波头、谐振腔体三个部分的设计方案,通过合理的结构设计完成了整机的研制,为探索脉冲微波的非热效应机理研究及应用提供了有利依据。     

一种新结构的硅基无源环形波导式谐振腔

提出了一种新结构的光学环形谐振腔。该谐振腔由四根直波导和四个拐弯角处集成的全反射镜围成一个方形环构成，这种结构免去了以前的波导式环形谐振腔中必需包含的弯曲波导。设计了谐振腔的输入和输出结构，并通过计算机辅助设计软件对该设计进行了优化。     

对称棱镜式环形谐振腔结构优化

由直角梯形棱镜构成的环形谐振腔的输出信号在机械振动环境下会受到影响,使输出波形幅值产生调制。为了改善谐振腔输出信号质量,从工程探索的角度出发,首次将对称型全反射棱镜纳入谐振腔的结构设计方案中。通过理论计算和有限元分析的方法,对比了两种谐振腔的光线传输特性和应力分布。结果表明,对于传输波长为632.8 nm的激光谐振腔而言,对称型结构可以保证构成谐振腔的光学元件具有对称的应力分布,降低棱镜上的应力双折射效应,提高输出信号的稳定性。对称性棱镜环形谐振腔的激光传输轨迹更稳定,装配要求更宽松,应力极值仅为非对称结构的15%。通过对比,在一个激励周期内,对称型谐振腔的激光输出能量波动相比原始结构降低了52.63%,平稳性获得了显著的改善。使用对称型环形谐振腔,对于提高我国现阶段环形激光传感器件的输出稳定性提供了一种新的技术途径。     

正交泊罗棱镜谐振腔

一、导论 激光测距机和指示器现正列入澳大利亚国防部的货单中。目前,这些装置的绝大部分是使用Nd:YAG激光。 武器系统研究室正在研制激光指示器系统,而先进工程试验室最近已为澳大利亚空军,完成激光测距机的可行性研究。 本报告是适应上述任务而写的,并为了修正激光器某些结论和评价泊罗谐振腔在电子试验室研制的激光深度探测器系统用的高重复频率（168Hz）激光器中有无优点。 “正交泊罗谐振腔”这一名称意思就是,两条屋脊线构成90°角。但并不总是如此,有时,屋脊线之间夹角可以不是90°,而这种装置仍称为正交泊罗谐振腔。 二、工作原理 2.1输出耦合 很多作者对正交泊罗谐振腔工作原理已进行过探讨,其中陈和泰波论述的最为详细。 在图1中,表示两种可能的激光器的结构示意图。图1（a）是从侧边输出的直线排列的系统,而图1（b）是具有轴向输出的折叠系统。这两个示意图原载于参考文献5和6中。     

角锥棱镜谐振腔输出模式模拟研究

为了探究角锥棱镜谐振腔输出模式的分布,在考虑角锥棱镜存在二面角加工误差的情况下,采用矩阵光学方法和矢量运算方法,建立了一套角锥棱镜反射模型,给出了角锥棱镜谐振腔输出模式的计算公式及数值模拟计算方法。用傅里叶变换方法和Fox-Li迭代法数值模拟得到了理想角锥棱镜谐振腔及存在二面角加工误差时的角锥棱镜谐振腔的输出模式。模拟结果表明:理想角锥棱镜谐振腔输出模式由六个均匀分布的对称的瓣状结构构成,而存在二面角加工误差的角锥棱镜谐振腔的输出模式中各个区域的强度分布不对称。     

扇调管输出环形腔的研究

扇调管是在偏调管基础上发展起来的一种高效率微波管。它的导流系数比偏调管的高,有可能工作于较低的束电压。相应地,它的输出腔则采用有双脊截面的环形腔。本文采用近似方法对这种环形腔进行了分析,详细介绍了它的设计及优化方法。最后,给出了模型腔的测试结果。它与理论计算基本吻合。     

“波导/自由空间”组合腔激光器的研究

研究了利用腔内空心波导管选横模的新方法的“波导/自由空间”组合腔激光器构型。实现组合腔“多横模振荡单横模高功率密度输出”的核心在于组合腔的自由空间增益区中足够大的多模振荡模体积和中空波导管所限定的最低阶波导模输出。理论上分析了组合腔的可行性和应用前景,并由实验结果所证实。     

Efficiency improvement of the traveling-wave interaction process

Experimental evidence that conventionally designed, uniform-period traveling-wave amplifiers are potentially highly efficient devices is presented. Experiments with a traveling-wave re-entrant cavity tube and with a two-helix tube show that substantial improvement is possible when the RF energy of the so-called beam of a saturated traveling-wave tube is used. Tests reported here on the two-helix tube realized efficiencies greater than 43 percent.     

The design of a microwave plasma cavity

The design of an efficient microwave plasma source is described. This source consists of a quartz tube surrounded by a cylindrical variable-length cavity which is connected to a 2.450-GHz power microwave source. The circuit performance of the plasma-cavity system is qualitatively explained and the lossy plasma-cavity eigenfrequencies are computed as functions of plasma density, effective collision frequency, and cavity length. Experiments demonstrate that a variable high-density plasma with densities in excess of 1000 critical densities can be sustained. Furthermore, by adjusting cavity length and coupling, microwave plasmas can be sustained in flowing and nonflowing argon gaseous environments from pressures of several microns to over one atmosphere.     

气体激光器圆柱形微波激励谐振腔的微扰理论分析及其应用

导出了工作于ＴＭ０１０模的圆柱形微波等离子体腔中等离子体与腔谐振频率关系的精确解析式和微扰近似公式，比较结果表明：在微波激励低气压气体激光器中微扰理论可相当精确地分析微波等离子体对腔的扰动效应。给出了消除等离子体与管壳的扰动引起的腔失谐的方法，从而在气体激光器中成功地形成了稳定与均匀的微波等离子体和稳定的激光输出。用微扰理论使此腔又具有测量等离子体电子密度和管壳微波介电常数的功能     

A 1-MW L-band coaxial magnetron with separate cavity

This paper describes an L-band coaxial magnetron using novel construction techniques. The tube is designed as a "plug-in" into a separate TE011mode cavity which controls frequency and allows external tuning. The magnetic circuit is complete within the tube package. The tube was designed to operate at 25 kV, which is quite low for this power level. It is believed that this design technique makes coaxial magnetron design at the lower frequencies practical. The total weight of cavity plus tube is less than 60 pounds. Power output of over 1 MW is achieved over 60 percent of the desired band of 1250 to 1350 MHz. Reduced power output is achieved over the remaining portion of the band.     

Efficient Methods for Determining the Coupling to Wires in Circular Cavities

The electromagnetic field coupling to a loaded thin wire in a cylindrical/coaxial cavity is investigated. Computationally efficient methods are presented for determining the coupling to a thin wire located near a cavity wall in a system of cascaded and/or overlapping coaxial and circular cylindrical cavity sections, and the accuracy and limitations of these methods are established. The sections are coupled through apertures and conducting elements common to more than one section, which may have different axial and radial dimensions and which may be filled with material having different magnetic and electric properties. The loaded thin wire is close to the outer wall of a cavity section and may represent a cable or, perhaps, a conducting tube. The coupling of the cavity field to the wire is determined from an analysis of a distributed voltage and current source model based on transmission line theory as well as via coupled integral equations techniques. The accuracy of the results obtained from these analyses is supported by experimental data measured on a laboratory model of the cavity-wire structure.     

Dynamics of Retrograde Electrons Returning From the Output Cavity in Klystrons

Loss of efficiency and tube oscillations have been attributed to electrons returning from the output cavity in klystrons due to excessive output cavity voltages. It is generally believed that the retrograde electrons lead to a relatively large harmonic current component in the input cavity, which overwhelms the input drive. Here, for the first time, detailed simulations describing the dynamics of retrograde particles for a nominal klystron design and cases with the shunt impedance of the output cavity increased, which show persistent harmonic bunching induced by the penultimate cavity, are presented. The maximum retrograde harmonic current is comparable to the current induced in the input cavity without the retrograde particles and can significantly influence the overall klystron behavior.     

The Key Technology of Efficiency Enhancement for Traveling Wave Tubes in Millimeter Wave

The efficiency enhancement methods for helix and coupled cavity traveling wave tube (TWT) in millimeter wave (MMW) are described. The interaction efficiency has been reached 14.56% by dynamic velocity taper in Ka-band TWT. Efficiency improvement has been carried out by used copper helix for broadband MMW TWT. Owing to a ferruleless coupled cavity TWT used phase-adjusted taper, the interaction efficiency has been increased from 9.6 to 22.6%. Finally, enhancing collector efficiency used multistage depressed collectors is discussed in the paper. These concept and technology of the approach are very useful for tube designer.     

回旋管模式选择复合腔的设计分析

为了使一种新型复合开放式谐振腔能够应用于毫米波回旋管器件,该文从工程设计的角度出发,分析这种腔结构中的公共壁增厚和轴向开漂移孔对腔中工作模式稳定性的影响,探讨在实际工程设计中补偿这种影响的手段。结果表明,合理增大复合腔外腔的半径能够有效实现工作模式的模式纯度和相对稳定性。