共查询到19条相似文献,搜索用时 93 毫秒
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利用正余弦拟合的方法和半径渐变波导的耦合波理论,设计出一种Ka波段TE01模回旋速调管带该新型渐变段输出腔。通过Matlab数值计算和HFSS仿真优化,研究了该新型渐变段的传输参数、反射参数、对杂模的抑制等性能指标。仿真结果表明:在渐变段长度为80mm、口径由14mm变化到32mm的情况下,在33~35GHz的范围内该新型渐变的传输参数大于-0.016dB,反射参数小于-55dB,对TE02模的耦合为-25dB和对TE03模抑制在-55dB以下;而该输出腔的中心频率为34.075GHz,Q值为109.6,工作模式TE01模式的模式纯度大于0.94。 相似文献
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在耦合波理论的基础上,详细讨论了3mm二次谐波渐变复合腔回旋管内置TE03—TE02—TE01模式转换器,并使模式转换器兼作回旋管的收集极.采用波纹波导结构和不同的相位重匹配技术进行优化分析,得到了可靠的最优几何参量.以此结果设计出了紧凑、高效的94GH z波纹波导模式转换器,并在回旋管的热测实验中测出模式样图. 相似文献
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本文提出一种分析金属覆盖渐变折射率光波导在止点附近的光学特性微扰近似方法,并仔细地讨论了金属覆盖指数折射率光波导在截止点附近的传播特性和截止条件。 相似文献
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为拓展工作带宽,以传统正反渐变槽天线为基础,利用基片集成波导馈电,该文提出了两种高增益、宽频带的正弦渐变槽天线。利用矩形波导3 dB定向耦合器和90移相器工作原理设计了半模基片集成波导单脉冲馈电网络,进而得到了对称型和非对称型正弦渐变槽单脉冲天线,带宽均超过了3.0 GHz,带内和波束最大增益在9.0 dBi左右,差波束零深在10.0 GHz处均低于-20 dB。其中,非对称型正弦渐变槽单脉冲天线具有更宽的工作频带和更平稳的天线增益,可以广泛应用于微波定向探测系统中。 相似文献
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本文给出一种新方法,用多层平板波导逼近非均匀平面波导,借助递推公式用牛顿切线法求解本征值方程,以求出非均匀平面波导导模的传播常数与模场分布。本方法优点在于程序简短通用,计算工作量小,求得结果与精确数值解十分吻合(直至近截止区)。本文给出了各种类型的非对称与对称渐变折射率平面波导的结果。 相似文献
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在回旋行波管的设计过程中,输出结构性能的高低直接影响到整管增益的高低以及输出功率的大小。采用切比雪夫渐变波导作为耦合输出段,通过对轮廓线的计算程序进行改进,将中心频率作为可变量进行了修正。仿真结果表明,长度为75mm改进后的切比雪夫渐变结构不仅能抑制工作模式向杂模TE02和TE03的耦合,还能有效减少工作模式的反射。在整个工作频段内,杂模TE02和TE03的耦合系数分别低于-33dB和-65dB,TE01模的反射系数低于-20dB,TE01模的传输系数高于-0.01dB。 相似文献
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Narendra Chauhan Ankush Mittal Dietmar Wagner M. V. Kartikeyan M. K. Thumm 《Journal of Infrared, Millimeter and Terahertz Waves》2008,29(8):792-798
In this paper the design and optimization of a nonlinear diameter taper, connecting the output section of a gyrotron cavity to the uniform output waveguide section, is presented. The design of a nonlinear taper of a 42 GHz, 200 kW CW gyrotron operating in the TE0,3 cavity mode with axial output collection has been taken as a case study. The taper synthesis has been carried out considering a raised cosine type of nonlinear taper and the analysis is done using a dedicated scattering matrix code. In addition, an improved particle swarm optimization - an evolutionary optimization - algorithm is used for the design optimization of this nonlinear taper. The optimum design of the taper shows the effectiveness of the presented method. 相似文献
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V. L. Bratman A. A. Bogdashov G. G. Denisov M. Yu Glyavin Yu K. Kalynov A. G. Luchinin V. N. Manuilov V. E. Zapevalov N. A. Zavolsky V. G. Zorin 《Journal of Infrared, Millimeter and Terahertz Waves》2012,33(7):715-723
The review summarizes recent experimental results in the field of THz gyrotrons developed for various applications. A CW gyrotron
with the operation frequency of 0.26 THz has been successfully used for DNP spectroscopy A pulsed high-harmonic Large Orbit
Gyrotron (LOG) with the frequency of 0.55 THz and kW level of output power has been used for THz breakdown and obtaining dense
plasma in gases. A powerful pulsed 0.67 THz/200 kW gyrotron is under development for remote detection of ionization sources. 相似文献
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The theoretical performance of two nonlinear circular waveguide tapers constructed for a 10-GHz, 30-MW amplifier utilizing the lowest circular electric mode is evaluated. Mode coupling is estimated with a code that solves the generalized telegraphist's equations numerically and is compared with the results of a cascaded scattering matrix code. It is found that assuming a sufficiently lossy conducting boundary allows evaluation of modes that pass through cutoff and that consideration of backward modes usually results in small changes in the forward modes that reconcile the two numerical procedures. A comparison of the raised cosine profile with other taper shapes is made. It is shown that, under some conditions, a raised cosine profile yields less mode conversion than the modified Dolph-Chebyshev profile 相似文献
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V. L. Bratman T. Idehara Yu. K. Kalynov V. N. Manuilov S. V. Samsonov N. A. Zavolsky 《Journal of Infrared, Millimeter and Terahertz Waves》2006,27(8):1063-1071
According to simulations, a Large Orbit Gyrotron with a 30 keV/1 A electron beam and magnetic field of 5 T can produce CW radiation with output power of 102?103 W at the frequencies of 0.4–0.5 THz. 相似文献
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非线性慢波电路中跳变幅度对饱和输出功率的影响 总被引:1,自引:0,他引:1
本文以罗埃大信号理论为基础,对提高小型化行波管效率的动态速度渐变技术和二次谐波的抑制问题进行了模拟计算分析。重点研究了非线性双跳变电路中跳变幅度的变化对饱和输出功率的影响。获得了实现动态速度渐变的最佳双跳变电路变化幅度。证明了在最佳跳变幅度,基波分量得到加强,二次谐波受到抑制,饱和功率在全频带范围(6~18GHz)内具有均衡输出。 相似文献
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提出了一种快速准确的新方法,用以计算入射场耦合到波导的能量.这种方法将BPM(beam propagation method)和叠加积分法结合起来,克服了单独用BPM计算场分布的效率较低的缺点,同时也克服了叠加积分只适用于计算规则波导的缺点,该方法称为正交过滤法.用这种快速方法对星型耦合器中输出波导的锥形波导形状曲线进行优化以获得最大的耦合能量. 相似文献
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在研究0.14 THz折叠波导行波管中,提出一种三段相速跳变的设计,使得电子能够在输出段与行波场发生速度再同步,从而提高了电子工作效率。根据色散公式,找到一种影响相速变化的结构因素。通过优化设计进行大信号程序计算,在电压14.95 kV、工作电流30 mA时,与未采用相速变化的结构相比,140 GHz时功率提高了0.84 W,效率提高了9.13%;在142 GHz时功率提高了0.88 W,效率提高了10.4%;-1 dB带宽由原来的5 GHz提高到7 GHz,扩展了行波管的带宽,提高了电子与波的互作用效率。 相似文献
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Toshitaka Idehara Jagadish C. Mudiganti La Agusu Tomohiro Kanemaki Isamu Ogawa Toshimichi Fujiwara Yoh Matsuki Keisuke Ueda 《Journal of Infrared, Millimeter and Terahertz Waves》2012,33(7):724-744
For application of high frequency gyrotron to high power THz technology, Gyrotron FU CW series is being developed in FIR FU.
Gyrotron FU CW CI is developed as one of sub-THz gyrotrons included in the series. The advantage of the gyrotron is compactness
using a compact superconducting magnet and compact power supply system, which makes the accesses of the gyrotron to applied
large-scale devices easier and extends the applications of gyrotron to wider fields. The designed frequency and cavity mode
are 394.5 GHz and TE26 mode for application to the 600 MHz DNP-NMR spectroscopy. As the operation results, the frequency and the output power were
394.03 GHz and around 30 W, respectively, which are available for the application to the 600 MHz DNP-NMR measurement. In addition,
this gyrotron can operate at many other frequencies and cavity modes for application to high power THz technologies in wide
fields. In this paper, the design and the operation results including long pulse or CW mode are presented. 相似文献
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扩展互作用振荡器由于具有结构紧凑、工作电压低、效率高等特点成为真空电子学太赫兹辐射源的重要研究
方向,在高分辨成像雷达、保密通信等方面具有广泛的应用前景。扩展互作用振荡器输出段是该器件输出THz 的关
键部分,其输出特性对扩展互作用振荡器的整体性能有着至关重要的作用。本文采用仿真软件模拟计算的方法,对扩
展互作用振荡器输出段的S 参数进行了较为详细的研究,并且对中心轴对称直渐变过渡波导、平面对称直渐变过渡波
导和阶梯过渡波导式结构的输出结构进行了比较研究,本文的结果对后续EIO 的设计与研究具有一定的参考意义和指
导价值。 相似文献