旭日型可调谐相对论磁控管的研究与优化设计

理论推导了相对论磁控管中电子与高频场的互作用机理,分析了相对论磁控管阴极发射面高度、工作电压和磁场对其工作效率及调谐带宽的影响,得出进一步提高磁控管效率及调谐带宽的条件。对比了10腔旭日型可调谐相对论磁控管仿真及实验结果,通过仿真手段进一步优化了该磁控管,提高了输出效率、拓展了调谐带宽。研究结果表明,优化后的10腔旭日型可调谐相对论磁控管具有37%的调谐带宽,电子转换效率最高达到17.9%,输出功率在1.1 GW以上。     

隔模带相对论磁控管的模拟研究

 提出了隔模带相对论磁控管(Strapped RM)的设想并对其提高效率的机制进行了分析和粒子模拟验证.通过对比Strapped RM与传统A6模型发现:隔模带的采用能够显著改变互作用区的场分布以减小强高频场对注波互作用的影响,降低阳极电流以减小阳极表面的电子注能量损耗,从而提高管子效率.粒子模拟得到Strapped RM的效率超过了70%,有效克服了传统RM的低效率缺陷.     

基于CHIPIC软件的旭日型可调谐相对论磁控管的研究

理论推导了相对论磁控管中电子与高频场的互作用机理,采用CST软件研究冷腔状态下磁控管的π模频率,采用CHIPIC软件对磁控管进行三维粒子模拟研究,对比了10腔旭日型可调谐相对论磁控管冷热腔仿真及实验结果,验证了CHIPIC软件模拟此类器件的正确性。研究结果表明,仿真结果与实验数据基本一致,频谱比较纯,输出比较稳定,为以后拓展旭日型可调谐相对论磁控管的调谐带宽奠定了基础。     

X 波段衍射输出相对论磁控管的粒子模拟研究

：本文报道了一个X 波段18 腔衍射输出相对论磁控管的初步模拟研究结果。利用高频场分析软件和粒子模拟软件, 通过分析和优化器件的结构参数,合理选取电磁场取值大小,最终得到：在二极管电压350 kV,外加磁场0.41T 条件下, 可以得到输出功率1.09 GW、功率转换效率为22%、频率9.59GHz 的微波。     

S波段磁控管阴极预群聚技术机理研究

阴极预群聚技术对磁控管的振荡建立过程具有显著的影响,但其作用机理仍然需要进行深入研究。本文对采用角向均匀分布的圆柱形多发射体阴极进行数值模拟,分析了互作用空间场分布及空间电子的运动规律,揭示了多发射体阴极与实体圆柱体阴极在磁控管的起振过程中存在显著差异。多发射体阴极的静电场角向分量与偏置磁场引入的洛伦兹力增强了初始阴极发射的电子向阳极漂移的能力。多阴极磁控管电子轮辐的外边缘更贴近阳极表面,群聚的电子在角向上具有周期性连续变化的速度分布,使得电子与高频场的能量交互更加充分。引入阴极预群聚技术的五阴极磁控管具有起振时间快、输出功率大、效率高等优点,从空间电场分布规律可知,阴极预群聚技术可降低布里渊半径,减少空间电荷对磁控管输出性能的影响。     

旭日型相对论磁控管的三维模拟

用两种3 维全电磁PIC 方法对10 腔旭日型相对论磁控管进行数值模拟。首先用MAGIC 对管子进行模拟,模拟结果表明：当工作电压为634 kV、磁场为0.53T 时,通过模拟该磁控管得到频率为2.6 GHz、平均功率为1.91GW的微波输出,平均效率为16.9 %。接着基于CHIPIC 平台进行模拟,通过与MAGIC 模拟结果进行对比,验证了CHIPIC在相对论磁控管中模拟的可行性,只是发现CHIPIC 在傅里叶变化命令设置上有些问题,需要进一步完善。     

轴向输出相对论磁控管真空室过渡段设计

相对于径向输出相对论磁控管而言,轴向输出相对论磁控管具有结构紧凑、高阻抗、角向均匀性、工作模式稳定以及高功率输出等一系列优点。但由于外加磁体对轴向输出端半径的限制,导致真空室的轴向长度大于磁控管的轴向长度,为了实现工程应用,一段较短的轴向输出过渡段被设计。文中主要是通过仿真软件仿真找到较为有效的过渡段设计以实现在S 波段π 模工作模式下的轴向输出相对论磁控管的能量有效输出。整个器件的轴向输出段的总长度为378 mm,输出端圆柱波导的半径为73.8 mm。在三维粒子模拟下得到一种较为有效的过渡段结构,功率转换效率为28.7%,相应的输出功率为1.371GW,辐射模式为TE01 模。     

微波加热沥青系统中辐射器结构的优化设计

先通过微波工作室CST软件仿真计算,并结合波导设计理论对某公司原有辐射器结构进行场分析,然后对磁控管的安装位置与辐射器结构进行了优化设计.优化后的结构与优化前相比较明显降低了反射,并得到了实验验证.此优化不仅满足了加热效率的需求,也有利于磁控管的寿命.     

磁控管中的空间电荷效应研究

对磁控管中由于外加磁场存在而导致的空间电荷效应进行了研究.通过求解正交场中的粒子运动方程,给出了阴极表面电位分布与外加磁场和阴极发射电流的关系,并指出磁控管中合适的发射电流是其最佳工作的前提.通过全电磁粒子仿真和实验测试证实了该效应对磁控管工作性能的影响,为高效率低噪声磁控管的研究提供了新思路.     

相对论全腔提取磁控管理论分析与数值模拟

本文研究了一种全腔提取结构透明阴极相对论磁控管,提取结构采用径向耦合孔与扇形波导耦合输出,结构更加 紧凑。我们用三维全电磁PIC 程序进行了数值计算,在1.38GHz,我们获得了近3GW的功率输出,效率超过了50%。     

Electromagnetic Field and Cutoff Frequencies of the Azimuthally Rippled Wall Waveguide

The cylindrical waveguide with azimuthally periodic corrugations described by a sinusoidal function is analyzed. Relevant to magnetron and gyrotron interactions, TE-mode oscillations are treated by deriving a dispersion relation—linking the cut-off frequency and corrugation parameters—upon expansion of the field quantities in terms of space harmonics. From numerical examples, the present paper examines how the geometrical properties (area and perimeter) of the corrugated cross section relates with the cutoff frequencies of 2π and π modes having one radial variation. The waveguiding system studied here with continuously corrugated azimuthal profile looks attractive to relativistic, slow-wave electron devices for it is more resistant to RF breakdown in comparison with traditional magnetron cavities with vane-type side resonators.     

间歇溅射和分段冷却对ZnO薄膜结构的影响

用超高真空射频磁控溅射技术制备了高c轴取向的ZnO薄膜,并用XRD和SEM研究了溅射和冷却方式对ZnO薄膜结构性能和工艺性能的影响。结果表明:与连续溅射相比,间歇溅射可以降低ZnO(002)的晶面间距,晶粒长大致密化,随着间歇时间的延长,薄膜的自优化程度增加;与连续冷却相比,分段冷却对ZnO薄膜的质量影响不大,但可将薄膜的冷却时间,从2.5~3 h缩短至1.5 h左右,从而提高了薄膜的制备速率。     

Quasi-optical gyro-peniotron at high cyclotron harmonics

This paper proposes a new kind of device operating at short millimetre wavelength, in which RF radiation generation is based on the interaction of a beam of sub-relativistic gyrating electrons and the RF standing-wave field of a quasi-optical resonator. This device can be called ‘quasi-optical gyro-peniotron’ because it is similar in electron-beam configuration, microwave circuitry and cyclotron resonance properties to the quasi-optical gyrotron and in its operational mechanism to the peniotron. Starting from relativistic equations of motion for the electrons, the calculation formulae are derived. Using computer simulation, a beam-wave interaction efficiency of 43% is obtained for the third cyclotron harmonic at frequency 100 GHz, beam voltage 80 kV and the applied magnetic field 13·3 kG, indicating that this tube will be potentially a high-efficiency high-power source not requiring a superconduction magnet system even within the 150 GHz band.     

Relativistic effect in electron cyclotron transverse wave devices

This note presents a simple physical argument which demonstrates the importance of relativistic electron bunching interactions between rotating electrons and an RF electric field in the plane of rotation, normal to a dc magnetic field. A magnitude comparison between the relativistic angular bunching and the well-known longitudinal bunching due to the transverse RF magnetic field shows that the close-to-cutoff operation of a number of recent cyclotron-frequency transverse-wave experiments is due solely to the relativistic effect.     

Analysis and Numerical Calculations of the Beam-Wave Interaction for Gyroklystron Amplifiers

A four-cavity gyroklystron was designed and optimized after analysis and calculation of RF system and magnetron injection gun, numerical simulations showed that the TE₀₁₁ mode gyroklystron achieved 280kW peak output power, 38% efficiency, 35dB saturated gain with 250Mhz bandwidth centered at 34GHz for a 68 kV, 11A electron beam. The numerical simulation results were used to build a Ka band high power gyroklystron amplifier. In this paper, analysis and numerical calculation results of the beam-wave interaction are presented. The influences of electron beam, RF system parameters, magnetic field, and input RF signal on output power, efficiency, bandwidth and gain are discussed.     

射频磁控溅射腔面镀膜半导体激光器的可靠性

利用射频磁控溅射法对半导体激光器的腔面镀 Si O2 膜 ,并对镀膜后的器件在恒定电流下进行了加速寿命实验 ,结果表明镀膜后器件的特性得到了很大改善。器件平均输出功率提高了 49.8% ,平均阈值电流下降了 7% ,平均斜率效率提高了 5 0 % ,而且射频磁控溅射方法所镀的膜具有粘附性好、膜层致密、厚度易控制、稳定性好、成本低等优点 ,器件的可靠性也有明显提高。     

A high-voltage modulator for high-power RF source research

The design, construction, and operating results of a high-voltage modulator system capable of generating 700-kV, 2.5-μs pulses at 5 p.p.s. into a load of 900 Ω are presented. The modular is used to energize a variety of high power microwave devices requiring voltage stability and reproducibility. Voltage ripple is less than 0.2% during the 1.0-μs flat top, with a shot-to-shot voltage variation of less than 0.1%. The primary circuit consists of two seven-stage tunable Rayleigh-type pulse-forming networks (PFNs) connected in parallel with a total impedance of 2.25 Ω, a total capacitance of 0.56 μF, and a total inductance of 2.8 μH. The PFN is charged by a highly stable 80-kV capacitor charging power supply (0.1% RMS voltage ripple) at a rate of 10 KJ/s. The total energy stored (1.5 kJ) is released through an ITT F-187 thyratron into a 20:1 pulse transformer, which generates 700-kV, 2.5-μs pulses. By changing the transformer, it was possible to obtain 250-kV, 1.70-kA pulses for driving low-impedance relativistic magnetron diodes. The flat-top voltage generated by the modulator is highly desirable for driving RF sources requiring high-quality electron beams, such as free-electron lasers (FELs) and cyclotron autoresonance masers (CARMs). The modulator performance in the relativistic magnetron and CARM experiments is described     

0.3T Ku波段返波管的低磁场特性研究

为了实现相对论返波管振荡器（RBWO）永磁包装,本文采用Magic模拟软件在0.5T低磁场相对论返波管（RBWO）器件结构基础上,通过在器件慢波结构末端添加一个部分反射腔,减小电子束质量对束波转换影响,即减小引导磁场的影响,实现了Ku波段相对论返波管振荡器0.3T磁场下运行.当电子束束压600kV、电子束束流7kA时,模拟得到器件输出微波功率740MW,效率18%.尽管该器件的效率低于0.5T磁场下的效率（25%）,然而0.3T引导磁场在工程上更容易实现.结合小型化的脉冲功率源进行实验研究,当二极管束压580kV、束流6.5kA,实验获得功率600MW,频率13.10GHz,脉宽25ns的微波输出,该器件的研制可以促进高功率微波（HPM）系统小型化的发展.