Based on it , a new kind of helix slow - wave structure named elliptical helix slow - wave structure used in helix traveling wave tubes has been detailedly investigated . by studying the rf characteristics of this slow - wave structure , it ’ s found that higher operation frequency and interaction impedance will be obtained by increasing the eccentricity of helix or decreasing it of the shield . meanwhile , great potential of improving system bandwidth has also been found if the eccentricity of helix or shield or the two are properly choosed 本文对近几十年大功率行波管的研究进展进行了简单讨论,并在此基础上研究了一种可应用于螺旋线行波管的新型的螺旋线慢波结构,即椭圆螺旋线慢波结构,通过对该螺旋线高频特性进行详细分析,我们初步认为,选择适当的螺旋线和屏蔽筒离心率,可以提高系统工作频率,增加系统耦合阻抗,并且具有改善系统带宽的潜力。
Owing to having the advantages of large size , good thermal conductivity , high precision of manufacturing and assembling , the all - metal slow - wave structures are widely used in the wide - band , high power traveling wave tube ( twt ) and relativistic twt . furthermore , the disc - loaded cylindrical waveguide is one of the most important slow - wave structures in the all - metal slow - wave structures ( sws ) 全金属慢波结构因其尺寸大、热耗散能力强、整体性能好等优点被广泛应用于宽带、大功率行波管和相对论行波管中,而膜片加载慢波系统正是全金属结构中最重要、应用最广泛的一大类结构。
Considering the influence of high evanescent modes , we have obtained the common theory . by the comparing between theoretical calculation and experimental data , we found the theory can accurately describe the high - frequency characteristic of this kind of slow - wave helical groove structure . then , five representative shapes are chosen and researched particularly ( triangle shape , cosine shape , trapezoid shape , rectangular shape and swallow - tailed shape ) 主要工作成果和创新之处在于: 1 .通过考虑高次模式的影响,获得了一种更为精确分析任意槽形螺旋槽结构的普遍理论,经与实验测量值比较,发现它更能准确可靠地描述此类螺旋慢波结构的高频特性,然后详细研究了五种槽形状(三角形槽、余弦形槽、梯形槽、矩形槽和燕尾形槽)对螺旋槽慢波系统导波特性的影响。
By a large amount of calculations , the influence of the structure dimensions and the dielectric parameters on dispersion characteristic and coupling impedance of this kind of slow - wave structure is obtained . then , the linear beam - wave interaction theories of the arbitrarily - shaped helical groove waveguide and the dielectric into the arbitrarily - shaped helical groove waveguide are deduced . by the numerical calculations , the relationship is got between the small signal gain , bandwidth , electromagnetic " hot " velocity and the electronic beam , the structural parameters 通过数值计算,获得了此类慢波结构的色散特性和耦合阻抗随结构几何尺寸和介质参数的变化规律;在此基础上,建立了任意槽形螺旋槽及中心加介质棒的任意槽形螺旋槽行波管的注-波互作用线性理论,并编制程序,计算了管子的小信号增益、带宽、电磁慢波的“热”相速与电子注参数、结构参数之间的关系,获得了增加带宽或增益的途径。
The slow - wave structure ( sws ) , as a key part of twt where the beam - wave interaction carries out for exciting microwave energy , determines its performance directly . with the development of techniques , novel slow - wave structures are needed to improve the performance of twt with higher power and wider bandwidth 随着科技的发展,人们对行波管的性能提出了更高的要求,更高的功率和带宽成为人们追求的目标,随着微波管向更高的频段发展,也要求有新型的慢波结构来提高行波管的性能。
Using the particle - in - cell ( pic ) model , a 8 millimeter relativistic backward wave oscillator underlying superradiance mechanism was gotten , the influence on both operation frequency and radiation efficiency of the guiding magnetic field , the diode voltage , the beam current and the beam radius as well as the corrugation structure were also presented 采用pic方法，通过数值模拟优化设计了超辐射状态下的8毫米相对论返波振荡器，分析了引导磁场、二极管电压、电子束流、电子束半径、周期慢波结构等对器件的辐射功率及辐射效率的影响。
