X波段同轴多注速调管优化及仿真

发布时间：2018-03-29 12:38

本文选题：X波段　切入点：多注速调管　出处：《电子科技大学》2015年硕士论文

【摘要】：本文对工作在TM310模式下的X波段同轴多注速调管进行了理论分析与粒子模拟。结合CST软件,对同轴谐振腔的特征进行仿真和理论研究,并测试冷腔参数。对X波段多注速调管的理论研究,包括速调管基本原理、小信号理论、大信号理论、谐振腔理论、收集极结构设计等。其中着重分析了空间电荷波理论、场波互作用、以及电子原盘理论等。依据理论计算出谐振腔结构参数、电参数等,并分析其对注波互作用和输出功率、频谱的影响。此外,还研究了收集极虚阴极现象的起因,提出有效解决方法,成功抑制住了电子回流现象。在理论上,结合CST软件对X波段速调管互作用段的工作特性进行研究。其中对TM310模的研究,分为三部分:一是计算谐振腔特征参数,例如工作频率、特征阻抗、品质因数等,并通过CST软件分析其与同轴谐振腔结构参数、漂移管结构参数之间的关系;二是分析速调管电参数,根据电压、电流密度和输入的高频信号等计算输出的功率、频率。调节输入、输出腔以及耦合孔结构,使之对应合适的工作参数;三是分析TM310模式下,X波段速调管谐振腔的场分布,同时计算间隙电场、耦合系数等。在仿真上,采用我国自独立研发的三维粒子模拟软件——CHIPIC,对整管进行仿真。研究速调管结构参数、电参数等与输出频率、功率和增益的关系。通过增大耦合孔半径将输出功率从33.6KW提高到39KW,通过增加损耗材料,抑制腔体自激振荡,将Q值从3000多降低至20以内,并拓展了速调管带宽。阴极发射6注束电流,电压21.5KV,总电流14.5A,电流密度358KA/m2。输入频率为9.75GHz、功率2.5W左右的高频信号,测得输出频率9.75GHz,输出功率约为100KW,滤波后输出功率为45KW,效率约为14%,增益约为42.6dB,带宽为200MHz。此外,本文根据CST软件的冷枪测试结果,研究了TM310模式,并引入短路杆解决了该模式的极化问题。对输入、输出腔场分布出现畸变的情况,本文引入调谐杆,不但使场分布重新恢复均匀,还增大了输出功率。通过CHIPIC软件里的动量、粒子瞬时相位图实时观测电子回流过程,分析并解决此现象。
[Abstract]:In this paper, the theoretical analysis and particle simulation of X-band coaxial multi-beam klystron working in TM310 mode are carried out. The characteristics of coaxial resonator are simulated and theoretically studied with CST software. The theory of X-band multi-beam klystron is studied, including the basic principle of klystron, small signal theory, large signal theory, resonator theory, collector structure design and so on. The structure parameters and electrical parameters of the resonator are calculated according to the theory, and the effects on the beam-wave interaction, output power and frequency spectrum are analyzed. In addition, the causes of the phenomenon of collecting the extremely virtual cathode are also studied. An effective solution is proposed to successfully suppress the phenomenon of electron reflux. In theory, the working characteristics of X-band klystron interaction are studied with CST software. Among them, the TM310 mode is studied. It is divided into three parts: one is to calculate the characteristic parameters of resonator, such as working frequency, characteristic impedance, quality factor, etc., and to analyze the relationship between the parameters of coaxial resonator and drift tube by CST software. The second is to analyze the electrical parameters of the klystron, calculate the output power and frequency according to the voltage, current density and the input high frequency signal, adjust the input, output cavity and the structure of the coupling hole, make it correspond to the appropriate working parameters; Thirdly, the field distribution of X band klystron resonator in TM310 mode is analyzed, and the gap electric field and coupling coefficient are calculated. The simulation of the whole tube is carried out by using the 3D particle simulation software-CHIPIC. the structural parameters, electrical parameters and output frequency of klystron are studied. The relation between power and gain. By increasing the radius of coupling hole, the output power is increased from 33.6KW to 39kW. By increasing the loss material, the self-excited oscillation of the cavity is restrained, and the Q value is reduced from more than 3000 to less than 20. And the bandwidth of klystron is expanded. The cathode emits 6 beam current, voltage 21.5KV, total current 14.5A, current density 358kA / m2. The input frequency is 9.75GHz and the power is about 2.5W. The output frequency is 9.75 GHz, the output power is about 100 kW, the output power after filtering is 45 KW, the efficiency is about 14, the gain is about 42.6 dB, and the bandwidth is 200 MHz. In addition, according to the results of the cold gun test of CST software, the TM310 mode is studied. The short circuit rod is introduced to solve the polarization problem of the mode. For the distortion of the field distribution in the input and output cavity, the tuning rod is introduced in this paper, which not only restores the field distribution evenly, but also increases the output power. The particle instantaneous phase map is used to observe the electron reflux process in real time, and this phenomenon is analyzed and solved.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN122

【参考文献】