共查询到19条相似文献,搜索用时 125 毫秒
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过模圆波导在提高功率容量的同时,不可避免地会造成微波源中同时存在多种模式。为了监测X波段长脉冲高功率微波源TM01模的输出功率和频谱,采用CST软件仿真设计了X波段高功率宽带选模定向耦合器,在耦合TM01模的同时可实现对TM02和TE11模的抑制。波导腔体及耦合孔的尺寸以小孔耦合理论和相位叠加原理为基础并结合切比雪夫分布函数计算确定。仿真结果表明:该高功率宽带选模定向耦合器在9.0~9.8 GHz的带宽范围内,耦合度为(-59.08±1) dB,定向性大于30 dB,对TE11模的抑制度大于15 dB,对TM02模的抑制度大于30 dB,功率容量大于2.5 GW。 相似文献
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从模式保留和转换的角度, 过模波导器件可分为模式转换器、模式保留器和模式综合器. 传统方法只解决其中一种器件的设计或者对器件的某个指标进行改进. 本文在深入分析耦合波理论之后, 提出了过模波导器件的迭代设计方法, 从原理上解决了过模波导器件的设计问题. 该方法能够统一设计三类过模波导器件, 通过添加不同的结构控制方法, 可得到转换效率更高、带宽更宽、结构更紧凑、满足不同工程需求的器件, 而且还能有效设计一些新型器件. 给出了两个设计实例: 双频TM01–TE11模式变换器和光壁馈源喇叭. 双频TM01–TE11模式变换器的两个工作频点为8.75 GHz和10.3 GHz, 波导半径为16 mm, 在两个频点转换效率为99%以上. 光壁馈源喇叭实现TE11模式向高斯束的转换. CST仿真结果验证了这两个器件设计的正确性和有效性.
关键词:
耦合波理论
模式转换器
模式过渡器
迭代法 相似文献
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基于不规则波导模式匹配法以及缓变波导中电磁波模式耦合理论,研究了一种W波段圆波导TE62模式激励器. 该波导模式激励器采用矩形波导TE10模式通过侧壁耦合馈入同轴波导,利用同轴波导的选模特性激励TE61模式;随后利用轴向半径周期微扰的圆波导实现TE61–TE62模式变换. 文中推导了矩形-同轴波导模式匹配理论,系统研究了波导结构缓变参数对模式变换效率的影响,完成了模式变换器的优化仿真设计,数值计算结果表明:中心频率处TE62模式的转换效率为94.5%,纯度为98.16%,效率85%以上带宽达到1 GHz,能够满足回旋管冷测的要求.
关键词:
同轴波导
模式变换
耦合模理论
半径微扰 相似文献
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基于几何光学理论和矢量绕射理论,研究了将回旋管及其他高功率微波器件的振荡输出模式转换成准光高斯波束的模式变换器,采用伏拉索夫(Vlasov)辐射器和三级准光反射面实现了准高斯模TEM00的横向输出.研究了Vlasov辐射器的工作机理,运用矢量绕射理论计算出波导辐射场,口面电流分布的方法计算反射面辐射场.通过编写程序设计了将94 GHz,模式为TE62的毫米波转化为准光高斯波束的内置式准光模式变换器.
关键词:
94 GHz回旋管
内置式准光模式变换器
Vlasov辐射器
矢量绕射理论 相似文献
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对比分析了几种可输出圆波导TE01模激励器的仿真设计结果。结果表明,利用行波功分结构实现矩形波导TE10模到4路矩形波导TE10模的等幅同相功分,进而合成转换成圆波导TE01模的转换过程,可在较宽的频带范围内,实现圆波导TE01模的高效激励。以中心频率9.40 GHz仿真设计的圆波导TE01模激励器,在中心频率上的传输效率超过99.9%;在9.08~9.61 GHz的频率范围内,传输效率大于99%。实验测量结果表明,所加工激励器在较宽的频带范围内,传输损耗优于-0.2 dB,与仿真结果的差异主要来自于波导壁面的欧姆损耗和波同转换结构;器件工作频带内平坦特性良好,有利于开展测量工作。 相似文献
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A numerical study of TM01-TE11 circular waveguide mode converter, with its optimized size and structure, is presented in this paper. Many factors such as spurious modes, backward wave, perturbation functions of waveguide axis or radius, phase-rematching techniques and ohmic losses are taken into account for the influence to mode converter's efficiency and bandwidth. And the dimensions of an optimized model (f0=35GHz. with input and output radius a0=13.6mm) are given. 相似文献
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Yasuyuki Itoh Tohru Sugawara 《International Journal of Infrared and Millimeter Waves》1996,17(2):465-475
This paper describes a quasi-optical method for the conversion of modes transmitted through highly oversized circular waveguides. A waveguide-mode is radiated once from a waveguide cut in the form of a radiation beam, which is then properly shaped by two curved mirrors and directed back into the waveguide. The curved mirror shapes are iteratively and automatically determined for given propagation distances using the design technique for phase correction mirrors. The proposed method gives favorable results in designing a waveguide expander/reducer, a TE01-TE02 mode converter, and a TE01-HE11 mode converter. 相似文献
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K. Ohkubo S. Kubo M. Iwase H. Idei M. Sato T. Shimozuma Y. Takita T. Kuroda 《International Journal of Infrared and Millimeter Waves》1994,15(9):1507-1519
Experimental measurements by wavepacket reflectometry are carried out to verify the low transmission loss of hybrid mode on HE11 in the corrugated waveguide with 88.9 mm in diameter. The HE11 mode is injected into the 62-m straight circular corrugated waveguide and the beat between the HE11 and HE21 (including degenerated TE01 and TM02) modes is observed. The loss is too small to measure and inferred to be less than 2 db/km. The result shows that the use of HE11 mode for electron cyclotron heating system is suitable. 相似文献
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Gregory G. Denisov Maxim L. Kulygin 《International Journal of Infrared and Millimeter Waves》2005,26(3):341-361
We study a transmission problem of an electromagnetic pulse with given transversal structure passing through a waveguide converter from TM01 to TE11 mode of circular waveguide. Using FDTD numerical simulation method we have investigated mode structure of the pulse at the output of the converter and its dependence on pulse length at the input. Also we have obtained frequency characteristic by calculating Fourier response for a pulse with wide spectrum. 相似文献
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John L. Doane 《International Journal of Infrared and Millimeter Waves》1993,14(2):363-382
The HE11 mode in corrugated circular waveguide can be converted to the EH11 mode (surface wave) by a short, smooth-waveguide phase shift section followed by a short corrugation depth taper. Low-power measurements at 110 GHz in 1.25 in. aluminum waveguide demonstrated approximately 99% conversion with the proper phase shift length. As expected, the conversion efficiency versus length of the phase shifter varied periodically with the period of the TE11 to TM11 beat wavelength. Since the EH11 surface wave is highly attenuated, this type of converter can be used effectively in a compact high-power dummy load. 相似文献
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作为小型化和紧凑型的高功率微波源,磁绝缘线振荡器(MILO)在过去十几年里得到了广泛的研究和发展.在大多数研究中,最低的对称模一直被当作器件的主模.然而,由于结构的对称性或者电子发射均匀度不理想等原因,很容易激励起非对称模式.计算了MILO同轴结构中同时包含对称模和非对称模的本征方程.在此基础上,通过对结构的优化设计,提出了一种HEM11模工作的MILO,并开展了原理性实验.在二极管的电压为480kV,电流为39kA条件下得到了功率为1.2GW,脉冲宽度为40ns的微波输出,功率转换
关键词:
磁绝缘线振荡器
高频特性
11模')" href="#">HEM11模
开放腔 相似文献
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Yin Li Chongqing Jiao Jirun Luo 《International Journal of Infrared and Millimeter Waves》2007,28(12):1155-1160
A mode converter with multi-waveguide output for millimeter wave gyro-device applications is proposed in this article, which
is used to convert the TE01 circular waveguide mode into the TE10 rectangular waveguide mode. Computer simulations with Ansoft HFSS code show that the energy transmission coefficient of larger
than 95.96% may be reached in the frequency range from 34.094 GHz to 35.8 GHz (a bandwidth of 1.706 GHz) at a VSWR of lower
than 1.5 for the input operating mode. 相似文献