共查询到19条相似文献,搜索用时 125 毫秒
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回旋行波管放大器是高功率毫米波雷达发射系统最重要的候选者.通过对回旋行波管放大器中的绝对不稳定性、回旋返波振荡以及电子注-波互作用的研究,讨论了回旋行波管的稳定性、寄生模式的抑制和工作参数的优化等问题,给出了W波段TE01模回旋行波管放大器的模拟设计结果.PIC粒子模拟结果表明,在电子注电压100kV、电流10A、工作磁场3.52T时,94GHz的基波回旋行波管放大器可获得大于250kW的输出功率、40dB的增益、大于25%的效率和约5%的带宽.
关键词:
W波段
回旋行波管放大器
模拟
设计 相似文献
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损耗介质波导对提高回旋行波管放大器的稳定性等性能具有积极的作用.本文基于损耗介质波导中工作模式的场表达式,推导出电子回旋脉塞互作用线性理论.通过系统的数值计算发现损耗介质波导与光滑金属圆波导中的工作模式从场型分布和色散关系上都具有一一对应关系;通过Laplace变换,利用互作用线性理论计算工作模式的起振场型和阈值,并研究互作用系统磁场、电流和介质层对放大特性的影响.这些研究成果对促进损耗介质在回旋行波管放大器中的运用和高稳定性回旋行波管放大器的发展具有积极的作用. 相似文献
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对70 GHz二次谐波倍频回旋速调管高频结构和电子与波互作用进行了研究。研究了TE02模腔体绕射品质因数及模式转化,解决了二次谐波倍频回旋速调管漂移段不能截止70 GHz的TE01模而引起的腔体间高频串扰的问题。分析了注电流、输入功率、电子横纵速度比和电子注引导中心半径等参数对输出功率、增益和效率的影响。针对二次谐波回旋速调管放大器工作频带窄、效率低,进行了高频结构优化设计,显著地展宽了工作频带,提高了互作用效率。在理论分析和高频计算的基础上,建立了注-波互作用PIC(粒子模拟)模型,进行了粒子模拟计算和优化,得到了70 GHz 的二次谐波倍频四腔回旋速调管放大器设计方案。粒子模拟结果表明:在工作电压70 kV,注电流13 A,电子注横向速度与纵向速度比为1.5时,中心频率69.81 GHz输出功率256 kW,带宽160 MHz,电子效率28%,饱和增益大于44 dB。 相似文献
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准光共焦波导具有功率容量大、模式密度低的特点,能够有效地减少模式竞争对回旋管互作用的影响,有利于高次谐波太赫兹回旋管的设计.为提高太赫兹准光回旋管的互作用效率,在共焦柱面波导的基础上,研究了一种新型高频互作用结构——双共焦波导结构,设计了一种330 GHz二次谐波双共焦结构回旋管谐振腔并对其进行了理论分析和粒子模拟.研究结果表明,双共焦谐振腔中的高阶模式能够与高次电子回旋谐波发生稳定的相互作用,并且没有模式竞争现象,具备工作在太赫兹波段的潜力.相比普通共焦波导谐振腔,双共焦谐振腔能够增强准光回旋管的注波互作用强度,提高回旋管的输出功率和工作效率.此外,结果还表明双共焦波导中的电磁波模式是一种由两个独立的共焦波导模式叠加而成的混合模式.利用这种混合模式有望实现太赫兹回旋管的单注双频工作,为新型太赫兹辐射源的研究提供了新的途径. 相似文献
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针对G波段真空电子器件对大功率、宽频带信号源的需求,开展了G波段三次谐波放大器研究。该放大器利用E波段行波管非线性互作用中的三次谐波电流,通过级联谐波互作用段实现G波段电磁波放大。高性能、实用化G波段宽频带大功率源的设计方案采用非半圆弯曲波导边界折叠波导,利用微波管模拟器套装(MTSS)软件对G波段三次谐波放大器进行模拟优化,结果显示,器件在15 GHz范围内可实现谐波输出功率>3.6 W,转换增益>33.3 dB,电子效率>0.36%。与其他工作在该频段的小型化太赫兹辐射源相比,谐波放大器在输出功率和带宽方面性能优越,为后续开展G波段三次谐波放大器的实际研制工作提供了设计基础。 相似文献
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详细推导了具有分布损耗波导结构的回旋行波放大器的色散特性。通过绝对不稳定性振荡出现的条件,给出求解具有损耗波导结构回旋行波管放大器的绝对不稳定性起振电流的数值计算方法。研究结果表明:绝对不稳定性起振电流与损耗波导的集肤深度有关,选择有较大的集肤深度的损耗波导可以提高绝对不稳定性起振电流;绝对不稳定性起振电流同时也与工作磁场偏离饱和磁场的程度以及电子束的纵横速度比有关;通过设计具有分布损耗波导结构的注-波互作用电路,以及工作磁场、电子束的纵横速度比,可以在兼顾带宽、效率的条件下,保证回旋行波管放大器稳定工作。 相似文献
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Wang Q.S. McDermott D.B. Luhmann N.C. Jr. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1996,24(3):700-706
The experimental results are reported for a stable second-harmonic gyrotron traveling wave amplifier, which generated a record-breaking 207-kW output power based on the principle that the weaker harmonic interactions are more stable to spontaneous oscillations than at the fundamental, and therefore, capable of generating higher output power. The high-power amplifier was kept completely (zero-drive) stable by employing a mode-selective interaction circuit and web-matched directional input and output couplers, and choosing an amplifier interaction length shorter than the start-oscillation length for gyrotron backward-wave oscillations. The single-stage Ku-band amplifier utilized an 80-kV 20-A υ⊥/υ∥=1.1 electron beam from a magnetron injection gun and yielded an efficiency of 12.9%, an output phase variation of 10°/kV, a saturated bandwidth of 2.1%, a large-signal gain of 16 dB, and a detuned small-signal gain of 38 dB 相似文献
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Chongqing Jiao Jirun Luo 《International Journal of Infrared and Millimeter Waves》2006,27(11):1427-1432
A self-consistent nonlinear theory is used to analyze the saturated performances of a Ka-band gyrotron traveling wave amplifier
(gyro-TWA) operating at the fundamental with a mode-selective interaction circuit involving a tapered vane-slot mode converter.
The amplifier is predicted to generate 140 kW saturated output power with 33.3% efficiency, a saturated gain of 33dB, and
a 3dB bandwidth of 2.7 GHz (8%) for a 70 kV, 6A electron beam with a velocity ratio of 1.0 and an axial velocity spread of
5%. 相似文献
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Kou C.S. Wang Q.S. McDermott D.B. Lin A.T. Chin K.R. Luhmann N.C. Jr. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1992,20(3):155-162
A linear theory using Laplace transforms which is applicable to both gyrotron traveling wave amplifiers (gyro-TWTs) and gyrotron backward-wave oscillators (gyro-BWOs) is presented. The validity of the linear theory is verified by comparing it with an existing nonlinear self-consistent theory based on a different approach. In conjunction with a time-dependent multimode particle simulation code, the linear theory is applied to study the stability of harmonic gyro-TWTs. It is shown that a harmonic gyro-TWT can be made stable to all forms of spontaneous oscillations by employing a multistage interaction structure and that it can generate power levels far in excess of those possible for a fundamental gyro-TWT. The linear bandwidth of a second-harmonic gyro-TWT amplifier is also calculated 相似文献
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Influence of Reflections of the Output Port on Beam-wave Interaction in Gyrotron Traveling Wave Amplifier 总被引:1,自引:0,他引:1
Haiyan Sun Chongqing Jiao Jirun Luo 《International Journal of Infrared and Millimeter Waves》2008,29(7):657-662
Based on the nonlinear self-consistent theory of gyrotron traveling wave amplifier (gyro-TWA), the influence of the reflections
of the output port with the taper on the beam-wave interaction in the gyro-TWA is studied. The simulation results show that
the reflections have great effects on the TE01 mode gyro-TWA operating at the fundamental. The influence of the taper angle and the interaction length on the beam-wave
interaction and the power profile is discussed and the corresponding physical mechanism is analyzed. The saturated output
power keeps same approximately with the increase of the taper angle in the presence of reflection while the saturated gain
decreases obviously. 相似文献
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定义了光子带隙谐振腔(photonic-band-gap cavity, PBGC)的等效半径,论证了使用该半径将PBGC等效为具有模式选择性的金属圆柱谐振腔的有效性,揭示了其在PBGC设计过程中的指导性作用.基于等效半径的运用,建立起光子带隙谐振腔回旋管振荡器(PBG回旋管)的自洽非线性理论,并对工作于TE32模的PBG回旋管作了理论分析和数值计算.目前的研究表明:高频电磁场沿角向呈行波或驻波的不同极化形式对PBG回旋管的注-波互作用过程具有较大的影响;较之电子回旋基波,该器件中二
关键词:
光子带隙谐振腔
等效半径
回旋管
自洽非线性理论 相似文献
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W-Band Second-Harmonic Gyrotron Traveling Wave Amplifier with Distributed-Loss and Severed Structures 总被引:2,自引:0,他引:2
Yi Sheng Yeh Chien Lun Hung Chi-Wen Su Ting-Shu Wu You-Yan Shin Yu-Tsung Lo 《International Journal of Infrared and Millimeter Waves》2004,25(1):29-42
The second harmonic TE02 gyrotron traveling wave amplifier (gyro-TWT) is a high-power, broadband, millimeter-wave amplifier with a low applied magnetic field. Mode-selective interaction circuits were applied to suppressing spurious oscillations. However, the mode-selective interaction circuit may perturb the operating mode in the gyro-TWT. A multi-stage gyro-TWT design with distributed-loss and severed structures is proposed to stabilize the amplification. This study presents a nonlinear analysis of typical oscillations, including absolute instability, gyrotron backward oscillation (gyro-BWO) and reflective oscillation. The lossy and severed sections of the multi-stage gyro-TWT seem to increase effectively the start-oscillation currents of the absolute instability, gyro-BWO, and reflection oscillation. The multi-stage gyro-TWT is predicted to yield a peak output power of 215 kW at 89.9 GHz with an efficiency of 14.3 %, a saturated gain of 60 dB and a bandwidth of 1.7 GHz for a 100 kV, 15 A electron beam with an axial velocity spread
z/
z = 5%. 相似文献