共查询到20条相似文献,搜索用时 0 毫秒
1.
2.
提出了一种类周期加载微波腔结构,通过理论和全电磁2.5维相对论粒子模拟程序计算,证实了电子束可以与这种谐振腔结构发生相互作用。基于该谐振腔特点,通过ASTRA程序(包含电子束自身空间电荷场的粒子运动模拟程序)设计和优化了一个X波段的类周期加载微波腔振荡器,该振荡器的束波转换效率理论值可达52%,工作频率为9.4 GHz。然后用全电磁2.5维相对论粒子模拟程序进行了进一步的优化,模拟中,输入电压700 kV,电流6.6 kA,磁场4.4 T,其输出功率为1.67 GW,束波转换效率达到36%。实验上输出微波峰值功率达到1.3 GW,脉宽26 ns,束波转换效率为26%。 相似文献
3.
The folded double-ridged waveguide structure is presented and its properties used for wide-band traveling-wave tube are investigated.Expressions of dispersion characteristics,normalized phase velocity and interaction impedance of this structure are derived and numerically calculated.The calculated results using our theory agree well with those obtained by using the 3D electromagnetic simulation software HFSS.Influences of the ridge-loaded area and broad-wall dimensions on the high frequency characteristics of the novel slow-wave structure are discussed.It is shown that the folded double-ridged waveguide structure has a much wider relative passband than the folded waveguide slow-wave structure and a relative passband of 67% could be obtained,indicating that this structure can operate in broad-band frequency ranges of beam-wave interaction.The small signal gain property is investigated for ensuring the improvement of bandwidth.Meanwhile,with comparable dispersion characteristics,the transverse section dimension of this novel structure is much smaller than that of conventional one,which indicates an available way to reduce the weight of traveling-wave tube. 相似文献
4.
采用多导体传输线分析方法, 对同轴交错圆盘加载波导慢波结构进行了理论分析, 得到了这种慢波结构的色散方程; 利用该色散方程, 得到的色散特性与HFSS仿真软件模拟结果符合良好. 分析了结构参数的变化对同轴交错圆盘加载波导慢波结构的色散特性影响. 结果表明: 增加内径和减小慢波结构的单位周期长度可以拓展慢波结构的带宽. 对同轴圆盘加载波导和同轴交错圆盘加载波导两种慢波结构的色散特性进行了比较, 结果表明: 采用圆盘交错加载方式可以减弱色散, 拓展带宽. 研究结果对同轴交错圆盘加载波导在毫米波行波管中的应用具有指导意义.
关键词:
行波管
同轴交错圆盘加载波导
慢波结构
色散特性 相似文献
5.
6.
7.
为实现渐变螺距螺旋线慢波结构高频参数的高精度估计,基于MAFIA仿真平台,研究了螺距变化对超宽带螺旋线慢波系统(4~18 GHz)的色散、互作用阻抗与衰减常数的影响,获得了各高频参数随螺距变化的规律。研究表明:相速几乎随螺距增大而线性变大,互作用阻抗与螺距是非线性的关系,衰减常数随螺距增大而非线性地减小;由于在维持电子注与电磁波速度同步的限制下,螺距变化的幅度不可能很大,因此可近似按线性关系来处理互作用阻抗及衰减常数与螺距之间的关系。由此提出了一种可精确计算渐变螺距螺旋线慢波结构高频参数的方法-线性插值法 相似文献
8.
Jianqiang Wu Shenggang Liu Yuanlong Mo 《International Journal of Infrared and Millimeter Waves》1995,16(12):2181-2194
On the basis of the reference [1], excitation of Cherenkov radiation with arbitrary azimuthal mode number by a thin annular relativistic electron beam in a plasma-filled dielectric-lined slow-wave waveguide is studied in this paper. A determinantal dispersion equation is obtained. This general dispersion equation is valid for arbitrary azimuthal mode number, and the growth rate of the wave is derived from it. Finally, the effects of the background plasma density on the dispersion relation, the background plasma density and the electron beam radius on the growth rate of the wave are presented. Formulas and results offerd in this paper are general, and are of particular value of reference to the beam-wave interaction in azimuthally unsymmetrical slow-wave waveguide.This work is supported by National Natural Science Foundation of China and 863 Project. 相似文献
9.
10.
A slow-wave structure (SWS) with two opposite gratings inside a rectangular
waveguide is presented and analysed. As an all-metal slow-wave circuit, this
structure is especially suited for use in millimetre-wave travelling wave tubes
(TWTs) due to its advantages of large size, high manufacturing precision and good
heat dissipation. The first part of this paper concerns the wave properties of this
structure in vacuum. The influence of the geometrical dimensions on dispersion
characteristics and coupling impedance is investigated. The theoretical results show
that this structure has a very strong dispersion and the coupling impedance for the
fundamental wave is several tens of ohms, but the coupling impedance for --1 space
harmonic wave is much lower than that for the fundamental wave, so the risk of
backward wave oscillation is reduced. Besides these, the CST microwave studio is
also used to simulate the dispersion property of the SWS. The simulation results
from CST and the theoretical results agree well with each other, which supports the
theory. In the second part, a small-signal analysis of a double rectangular
waveguide grating TWT is presented. The typical small-signal gain per period is
about 0.45 dB, and the 3-dB small-signal gain bandwidth is only 4\%. 相似文献
11.
将任意形状槽的连续轮廓近似用一系列相连的矩形阶梯近似,利用各阶梯面上导纳的匹配,以及槽与互作用区边界场的连续与匹配条件,获得了具有任意槽的矩形波导栅慢波结构的色散方程和耦合阻抗的表达式,并进行理论上的验证.加工制作了矩形槽波导栅模型,冷测表明理论值与测量值相吻合.分别求解几种特殊槽形矩形波导栅慢波结构的色散特性及耦合阻抗,其中,三角形结构的色散和耦合阻抗均最弱,而倒梯形结构色散最强,耦合阻抗最大.
关键词:
矩形波导栅
任意槽
色散特性
慢波结构 相似文献
12.
A watt-class backward wave oscillator is proposed,using the concise sine waveguide slow-wave structure combined with a pencil electron beam to operate at 220 GHz.Firstly,the dispersion curve of the sine waveguide is calculated,then,the oscillation frequency and operating voltage of the device are predicted and the circuit transmission loss is calculated.Finally,the particle-in-cell simulation method is used to forecast its radiation performance.The results show that this novel backward wave oscillator can produce over 1-W continuous wave power output in a frequency range from 210 GHz to 230 GHz.Therefore,it will be considered as a very promising high-power millimeter-wave to terahertz-wave radiation source. 相似文献
13.
A microwave propagating along vacuum—dielectric—plasma interface excites surface plasma wave (SPW). A periodic slow-wave structure
placed over dielectric slows down the SPW. The phase velocity of slow SPW is sensitive to height, periodicity, number of periods,
thickness and the separation between dielectric and slow-wave structure. These slow SPW can couple the microwave energy to
the plasma and can sustain the discharge. The efficiency of the power coupling is few per cent and is sensitive to separation
between dielectric and slow-wave structure. 相似文献
14.
15.
16.
17.
18.
设计了一种新型L波段慢波结构式圆波导TM01-TE11模式转换器,该转换器的尺寸为φ15.0 cm×40.8 cm,通过金属分割片将圆波导分成两个180°区域并在其中一个区域内设置半环形慢波结构。当TM01入射时,在两个区域内激励起扇形波导TE11模式,由于慢波结构的存在,该模式在两个区域内的传播常数不一样。适当调节慢波结构的参数,可使两个区域内传输的扇形TE11模式在金属分割片尾部相位相差180°,这两个扇形TE11模式耦合成为圆波导TE11模式输出,实现模式转换。建立数值模型并进行了模拟,结果表明在工作频率1.8 GHz处转换效率96%,反射率低于0.04,功率容量超过1.7 GW。 相似文献
19.
用阶梯近似的方法分析任意槽形加载的圆波导慢波系统,利用各阶梯相邻面的导纳匹配条件 以及中心互作用区与加载区的场匹配条件,获得了任意槽形加载周期慢波结构的统一色散方 程. 利用该色散方程,得到色散特性与CST MWS仿真软件模拟结果良好符合. 分别求解几种 特殊槽形加载慢波结构的色散特性及耦合阻抗,其中,三角形结构色散和耦合阻抗均最弱, 而倒梯形结构色散最强,耦合阻抗最大.
关键词:
任意槽形
慢波结构
色散特性
行波管 相似文献