圆形槽波导到矩形波导结的有限元分析

设计基于圆形槽波导的元件经常会用到圆形槽波导到矩形波导结.应用有限元法(FEM)分析了N端口波导结.采用完全匹配层(PML)将槽波导的开放边界截断为有限区域,然后对圆形槽波导到矩形波导结的散射特性进行了数值计算,得出的散射参量为圆形槽波导振荡器输出结构的优化设计提供了依据.     

圆形槽波导的􀀂 FDTD 分析

圆形槽波导^[1]是一种新型的宽频带、大功率，低损耗和大尺寸波导结构，在毫米波、亚毫米波波段有重要应用前景。利用时域有限差分法（FDTD）分析了圆形皮导的传输特性，计算了圆形槽波导工作在主模TE^[1]11情况下的色散曲线和截止频率，并与已知的理论值相比较，两者一致性好。     

小孔耦合在圆形槽波导中的应用

本文应用电磁场的互易原理以及小孔辐射的工程处理方法 ,分析了不同尺寸圆形槽波导间的小孔耦合情况 ,得到了小孔等效感抗公式 ;然后 ,讨论了圆形槽波导与圆形槽波导腔之间的小孔耦合情形 ;最后 ,进行了数值计算 ,并与实验结果进行了比较 ,二者吻合 ,从而证明了理论分析方法的正确性。     

圆形槽波导中径向盘直径对阻抗的影响

为了设计W波段的圆形槽波导中径向盘结构,采用有限元分析方法和完全匹配层(PML)的概念,对W波段的圆形槽波中径向盘处于非中心位置时输入阻抗随径向盘直径的变化进行了计算,并给出了变化曲线。在94GHz时径向盘直么在0．6mm～0．8mm范围内输入阻抗最小。计算结果能够为设计w波段圆形槽波导振荡器提供参考。     

新型圆形槽波导定向耦合器

圆形槽波导是一种新型的高功率毫米波、亚毫米波传输线.为了实现圆形槽波导之间的耦合,本文根据双槽波导的耦合机理,设计出了新型圆形槽波导走向耦合器,并计算了3dB圆形槽波导定向耦合器的频率特性.     

介质加载圆形槽波导的分析

采用矢量基函数的有限元方法，在开放边界处采用完全匹配层(PML)截断无限区域。分析了在圆形槽波导不同位置加载平板状介质时的模式特点。分析表明介质加载时圆形槽波导的模式次序要发生变化，为设计圆形槽波导微波化学反应器提供了依据。     

圆形槽波导中径向盘的位置和厚度对输入阻抗的影响

介绍了复杂边界条件的圆形槽波导的有限元分析方法和边界处理方法。利用完全匹配层(PML)对圆形槽波导的开放边界进行截断,应用有限元法计算W波段圆形槽波导中径向盘位置和厚度对径向盘输入阻抗的影响,数值结果的分析可供设计圆形槽波导中径向盘时参考。     

圆形槽波导中径向盘厚度对阻抗的影响

应用时域有限差分法(FDTD)计算圆形槽波导中径向盘输人阻抗。用一种简单方法来近似圆形槽波导的曲线金属边界。完全匹配层(PML)应用于圆形槽波导的开放边界。用细网格计算我们关注的径向盘中的场值。最后,由电压和电流的傅立叶变换的比值得到随径向盘厚度变化的输人阻抗。     

圆形槽波导中径向盘对阻抗的影响

应用时域有限差分法(FDTD)计算圆形槽波导中径向盘直径、厚度、位置对输入阻抗的影响。用非均匀网格和三角形网格来近似计算圆形槽波导的圆弧形金属边界附近的场值,用细网格计算径向盘中的场值,用完全匹配层(PML)模拟圆形槽波导的开放边界。最后由电压和电流的离散傅立叶变换的比值得到随径向盘直径、厚度、位置变化的输入阻抗。     

圆形槽波导的一种简单分析方法

把圆形槽波导等效成横向传输线网络,用不同的均匀传输线等效圆形槽及两边的平行平板区域,根据横向谐振条件,利用Runge-Kutta数值计算方法,分析了波导的色散关系.得到了归一化截止波长λc/2a与归一化波导尺寸2c/2a,以及传播常数β与频率的关系曲线.该分析过程简单明了,数值分析的结果与相关文献的结论吻合较好,表明这...     

The wide band property of circular groove guide

According to the analyses of the moding properties of circular groove guide, the guide dimension for single mode operation is determined. Our results show that circular groove guide has the advantage of wide band.     

Wide-band circular groove guide horn antenna

A novel horn antenna based on a circular groove guide is analyzed and measured at Ku-band and Ka-band, respectively. This horn antenna can cover a frequency range from 14 to 40 GHz. Its optimum dimension was obtained according to the maximum directivity. The antenna can be matched efficiently to free space through its large aperture. Moreover, its input VSWR is low. The theoretical radiation patterns are close to the measured ones.     

曲折矩形槽波导慢波系统的高频特性

对曲折矩形槽波导新型慢波系统的高频特性进行了研究，通过理论分析和数值计算，得到了它的色散曲线和耦合阻抗，并分析了结构参数变化时对色散特性和耦合阻抗的影响。曲折矩形槽波导结合了曲折波导散热能力强、色散特性好、容易加工和矩形槽波导单模工作、低损耗、大尺寸等优点，因此这种新型的慢波系统有可能在毫米波及亚毫米波段的行波管中具有较好的发展前景。     

Finite Element Analysis of Field Pattern in Multiple Groove Guide

Rectangular groove guide with multiple grooves has been analyzed by finite element method (FEM) in this paper. The electrical field patterns of the dominant mode and the first higher-order TE mode have been presented for groove guide with single-, double-, triple-, and quadruple-rectangular grooves. The electromagnetic field of the dominant mode is distributed with a concentration in the groove regions, while the electromagnetic field of the first higher-order TE mode is mainly distributed in regions between grooves. The low loss characteristic has been found not only in single-groove guide, but also in multiple groove guide.     

Circular groove guide for short millimeter and submillimeter waves

A new type of groove guide, circular groove guide, has been designed for use as a low losses, high power handling, low dispersion and single mode transmission medium in the short millimetric and submillimetric waves ranges. The characteristic equations of TE modes and TM modes have been developed and the propagation characteristics of the fundamental mode have been discussed. Experimental measurements are in good agreement with theoretical results     

Dominant mode characteristics of circular groove guide

Circular groove guide is a kind of waveguide for millimeter waves with low loss, large dimensions, and low dispersion. In this paper, the dominant mode characteristics of it is analysed. The technique that mode macthing method combines with point matching method is used to derive the Nth-order characteristic equation of the guide. The 1st order, 2nd order and 3rd order approximate curves that the normalized cutoff wavelength of circular groove guide varies with c/a are given. The attenuation curves are given at 1mm, 1.5mm and 3mm wavelength. The numerical results are in well agreement with the experimental results published.     

Finite Element Analysis of the Dominant Mode Variation in Groove Guide

In this paper, the dominant mode in groove guide is analyzed by finite element method. For the guide with a shallow groove, the electric field lines (abbreviated as E lines) are perpendicular to the parallel plate, which is different from the literatures, and the dominant mode distribution is irrelevant to the groove width; for the guide with a narrow but deeper groove, the E lines are parallel to the plate region, which represents the characteristics of lower attenuation, for the guide with a deeper and wider groove, a complicated E lines are obtained. These results reveal that the dominant mode distribution in groove guide is varied, which replenish our understanding of groove guide, and the results have important values in design, manufacture, and application of groove guide.