W 波段回旋行波管双阳极磁控注入电子枪的设计

回旋行波管是大功率、高频率的微波毫米波器件。根据W波段回旋行波管的要求,设计了双阳级磁控注入电子枪。由电子光学理论,计算得到电子枪的初始参量,然后利用粒子模拟软件MAGIC构造电子枪模型,分析电子枪各个参数对电子注性能的影响,为电子枪设计优化提供了一定的依据。最后优化得到符合设计要求的低速度零散电子枪结构。电子枪阳极电压为70kV,电流10A,电子注速比1.07,电子注横向速度零散0.8%。     

回旋行波管高质量阴极及电子枪研究

回旋行波管对回旋电子注参数（纵横速度比、速度零散等）非常敏感,实验中需进行电子参数调节,高质量电子枪研制是整管设计核心之一。基于理论分析、结构分析及热分析等对回旋行波管电子枪进行改进设计,对阴极、热子进行优化设计,研发的电子枪速度零散＜2%,优于国际报道的3%。项目在热分析和形变分析基础上,改进了阴极结构及制备工艺,显著提高了热子加热效率,将阴极加热功率从100W降低至50W左右,提升了阴极发射的均匀性和稳定性,10%工作比下长时间工作稳定、可靠,有效保障了阴极寿命,新研电子枪在Ka频段回旋行波管装管实验,脉冲功率100kW,平均功率10kW,连续工作稳定、可靠。     

大屏幕彩色显像管电子枪聚焦性能分析

电子枪聚焦性能是由电极结构决定的。本文通过计算机模拟的方式对三种典型的用于大屏幕彩色显像管电子枪的光点形貌进行了系统模拟。对各电子枪聚焦特性进行的分析和比较表明电子束形成区、主透镜结构对屏蔽中心、角部的着屏光点及不同电流下聚焦的稳定性都有较大的影响。     

功率行波管栅控电子枪振动模态特性与结构可靠性

介绍了功率行波管栅控电子枪的实际结构和振动考核要求,分析了电子枪的自由振动模型,并根据试验模态数据,分析了电子枪的模态频率及振型对枪体结构可靠性的影响。     

大屏幕彩色显像管电子枪聚焦性能分析

电子枪聚焦性能是由电极结构决定的，本文通过计算机模拟的方式对3种典型的用于大屏幕彩色显像管电子枪的为形貌进行了系统的模拟，对各电子枪聚焦特性进行了分析和比较表明电子束形成区，主透镜结构对屏幕中心，角部的着屏光点及不同电流下了聚焦的稳定性都有较大的影响。     

28 GHz低速度离散回旋管电子枪三维电磁设计

磁控注入电子枪可以产生具有角向旋转速度分量的电子束,是回旋管的核心部件之一,其性能优劣直接决定了整管的系统性能。本文首先分析了两种典型的磁控注入电子枪结构,根据28 GHz回旋管互作用腔束-波互作用工作需求,设计了一种双阳极结构的电子枪。三维粒子仿真设计结果表明,在阴极电压40 kV、调制阳极电压18.2 kV、电流3.2 A的条件下,引导中心半径为3.2 mm,横纵速度比为1.5,横向速度离散达到了1.06%。与此同时,所设计的电子枪具有较大的工作区间,在横纵速度比为1.9时,横纵速度比离散依旧能够达到不高于5%的要求。     

高性能阴极射线管用电子枪设计的一种新方法

本文描述了阴极射线管所用的一种新型电子枪结构，同时就其它电子枪，即传统设计的电子枪和近来高性能电子枪类型作了比较。     

磁控注入电子枪低频振荡分析

电子枪低频振荡对电子注速度零散有很大的影响。本文对磁控注入电子枪中低频振荡现象进行了分析。通过理论分析简述了电子枪中低频振荡的形成过程以及束缚电子对电子枪区空间电势的影响。利用PIC(粒子模拟)编程分析了电子注电流对低频振荡的影响。提出了通过改变绝热压缩区的磁场分布,达到抑制低频振荡的目的。     

大回旋电子注双磁会切电子枪的数值模拟

该文分析了双磁会切电子枪的理论模型,建立了会切磁场模型,采用EGUN和MAGIC模拟,设计出了产生大回旋电子注的双磁会切电子枪,该枪的电子注速度比为1.38,轴向速度零散为3.7%。文中分析了电子注速度比、速度零散沿轴线的分布情况,进而讨论了不同的会切磁场变换宽度对电子注参量所带来的影响,为双磁会切电子枪设计的参量选择提供了依据。     

W波段回旋行波管新型曲线阴极磁控注入电子枪优化设计

设计了采用新型曲线阴极结构的W波段双阳极磁控注入电子枪,手动优化得到的电子注参数在速度比1.1时,纵向速度零散为1.84%.为了克服手动优化方法的繁琐和低效,引入了数值计算方法的优化策略,编制了基于MATLAB语言的遗传算法和模拟退火算法的优化程序,并结合二维电子光学软件EGUN对该W波段曲线阴极结构电子枪进行优化,优化得到的电子枪在保证电子注速度比1.1的情况下,纵向速度零散分别达到了0.81%和1.05%.与手动优化方法相比,数值优化方法不需要设计者干预优化过程,具有自动高效的特点,且优化结果更好.     

Design of a Temperature Limited Single-Anode Magnetron-Injection-Gun

A single-anode magnetron-injection-gun which will be employed to high power (61.5kV, 2amps) gyro-amplifier experiments is designed. Analytic equations based on adiabatic theory and angular momentum conservation are used to examine initial design parameters such as cathode angle, beam emitting surface radius, and anode-cathode gap. A final beam optics optimization is carried out by the use of an electron trajectory code. A beam rms spread of axial velocity, Δv _z/v _z, obtained from the ray tracing code is observed to be 3.7% at α = 1.37. Cathode surface roughness and thermal spreads result in increasing the beam velocity spread to 4.2%.     

基于信号子空间处理的和/差波束干涉SAR/GMTI技术研究

该文研究了和/差波束干涉SAR/GMTI技术在通道不平衡条件下地杂波对消问题.文中阐述了和/差波束干涉SAR/GMTI的原理,推导了理想条件下地杂波空域对消因子.实际系统中,由于存在通道幅相不一致等误差,直接空域对消并不能有效抑制地杂波.该文研究了基于信号子空间处理的和/差波束干涉SAR/GMTI方案,通过二维信号子空间处理自适应地校正通道误差,进而对地杂波进行空域对消.仿真实验表明该方案对系统误差的敏感度显著下降,具有很好的鲁棒性,更适合于工程实施.     

Numerical Simulation of a Double-anode Magnetron Injection Gun for 110 GHz, 1 MW Gyrotron

A 40 A double-anode magnetron injection gun for a 1 MW, 110 GHz gyrotron has been designed. The preliminary design has been obtained by using some trade-off equations. The electron beam analysis has been performed by using the commercially available code EGUN and the in-house developed code MIGANS. The operating mode of the gyrotron is TE_22,6 and it is operated in the fundamental harmonic. The electron beam with a low transverse velocity spread (db _^max = 2.26% \delta {\beta_{ \bot \max }} = 2.26\% ) and the transverse-to-axial velocity ratio of the electron beam (α) = 1.37 is obtained. The simulated results of the MIG obtained with the EGUN code have been validated with another trajectory code TRAK. The results on the design output parameters obtained by both the codes are in good agreement. The sensitivity analysis has been carried out by changing the different gun parameters to decide the fabrication tolerance.     

Design comparison of single-anode and double-anode 300-MW magnetroninjection gun

Analytic tradeoff equations based on adiabatic assumptions are used to explore feasible design regions for single-anode magnetron injection guns (MIGs). Particle simulations are then used to optimize a single-anode and a double-anode design for a 1-μs, 500-kV, 600-A MIG which is required for a second-harmonic gyroklystron. The advantages and disadvantages of each configuration are critically examined     

Study of a Ka-Band TE11 Mode Gyrotron Traveling-Wave Amplifier

A Ka-band gyrotron traveling wave (gyro-TWT) amplifier with high power and wide bandwidth operated in the fundamental TE11 circular mode is presented in detail. The stability of the gyro-TWT amplifier using linear and nonlinear theory is analyzed. The distributed loss technique is employed in the interaction circuit which guarantees the amplifier zero-drive stability. The effects of the parameters such as input power, driver frequency, magnetic field on the performance of the gyro-TWT is discussed. The simulation results show that the gain and the bandwidth of the designed Ka-band gyro-TWT are about 60.0 dB and 1.4 GHz at constant drive with an axial velocity spread Dv_z \mathord

W波段四腔回旋速调管放大器

介绍了W波段四腔回旋速调管放大器的设计.放大器工作在基膜TE01圆电模式,电子束工作电压70 kV,工作电流6A,设计的双阳极磁控式注入电子枪,电子束纵横速度比1.5,速度零散小于4％.采用粒子模拟方法分析了各种参数对器件性能的影响.模拟结果显示,设计的放大器在电子束速度零散4％的情况下,增益35 dB,带宽800 MHz,输出功率100 kW,效率为23.8％.     

Design of a Double Anode Magnetron Injection Gun for Q-band Gyro-TWT Using Boundary Element Method

This paper presents a novel design code for double anode magnetron injection guns (MIGs) in gyro-devices based on boundary element method (BEM). The physical and mathematical models were constructed, and then the code using BEM for MIG’s calculation was developed. Using the code, a double anode MIG for a Q-band gyrotron traveling-wave tube (gyro-TWT) amplifier operating in the circular TE₀₁ mode at the fundamental cyclotron harmonic was designed. In order to verify the reliability of this code, velocity spread and guiding center radius of the MIG simulated by the BEM code were compared with these from the commonly used EGUN code, showing a reasonable agreement. Then, a Q-band gyro-TWT was fabricated and tested. The testing results show that the device has achieved an average power of 5kW and peak power ≥?150 kW at a 3% duty cycle within bandwidth of 2 GHz, and maximum output peak power of 220 kW, with a corresponding saturated gain of 50.9 dB and efficiency of 39.8%. This paper demonstrates that the BEM code can be used as an effective approach for analysis of electron optics system in gyro-devices.     

Computer Simulation of Axis-Encircling Beams Generated by an Electron Gun with a Permanent Magnet System

Results from computer aided design of a novel electron gun generating axis-encircling beams are presented and discussed. Numerical experiments were performed by the new version of the software package GUN-MIG named GUN-MIG/CUSP. It is based on a self-consistent relativistic model and is developed as a problem oriented tool for analysis of electron-optical systems with magnetron injection guns (MIG) and electron guns with field reversal (cusp guns), forming axis-encircling beams. As a result of the simulations an electron-optical design of a novel electron gun with permanent magnet system was accomplished. The gun is expected to form high quality beams with small velocity spread and beam ripple. Parameters of the generated beams are appropriate for a prospective weakly relativistic high harmonic large orbit gyrotron (LOG). The development of such device is in progress now at the Research Center for Development of Far-Infrared Region (FIR Center) at Fukui University.     

Self-consistent Nonlinear Analysis and 3D Particle-In-Cell Simulation of a W-band Gyro-TWT

The self-consistent nonlinear analysis and CST 3D particle-in-cell (PIC) simulation of a W-band gyrotron traveling wave tube (gyro-TWT) are presented in this paper. Both the simulation results of the two codes are excellent agreement with each other. The gyro-TWT loaded with periodic lossy dielectric in the circuit for suppressing potential spurious oscillations. It is driven by a 70kV, 10A gyrating electron beam with velocity ratio of 1.0. PIC simulation results are: the maximum peak output power of 198kW, statured gain of 62.3dB and efficiency of 28.3% at 92.5GHz. Only the operating mode TE ₀₁ is observed in the CST 3D simulation and the potential competing backward wave oscillations are effectively suppressed. The CST simulation also predicts that the device works stably under the condition of the beam current lower than 14A and B ₀ /B _g lower than 1.05. The simulated bandwidth with peak power greater than 100kW is 6.8GHz without axial velocity spread, and 4.1GHz with 6% axial velocity spread.