共查询到19条相似文献,搜索用时 187 毫秒
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对太赫兹波在椭圆波导中的Helmholtz波动方程进行研究,结合Mathieu函数,给出了在椭圆坐标系下电磁波的场函数,并最终获得太赫兹波在椭圆波导中的主模衰减特性。结果发现椭圆波导长轴和离心率越小,则衰减越大。 相似文献
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本文对椭圆波导TE01-TE11模式转换器进行了研究。选择了合适的椭圆波导截面,在椭圆波导纵轮廓线函数中采用了相位重匹配方法,并利用粒子群算法进行了纵轮廓线优化,所设计的椭圆TE01-TEs11模式转换器在28 GHz时的转换效率为99.16%,在27~29.3 GHz模式变换器的效率大于90%,相对带宽为8.2%。所设计的TE01-TEs11椭圆模式转换器的转换段为现有长度的一半。将设计的椭圆模式转换器与两个过渡段相连,并在CST中进行仿真和验证,其结果与理论计算一致。设计出了一个中心频率点为28 GHz的高效、紧凑、高功率椭圆波导TE01-TE11模式转换器。 相似文献
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为340 GHz 返波振荡器设计了输能窗,并对其进行了设计分析及仿真模拟计算.计算结果表明,该窗在327 GHz-347 GHz 频段内的反射系数优于30 dB.对窗片进行金属化,焊接输能窗,封接出气密性良好的输能窗,对输能窗进行测试.测试结果表明,该窗在333 GHz-367 GHz频段内反射系数优于10 dB,其中,在336 GHz-344 GHz 频段内优于15 dB,传输损耗7 dB 左右.对模拟结果与实测结果的偏差进行了分析,为进一步优化输能窗奠定基础. 相似文献
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椭圆波导中的cE01模 总被引:1,自引:1,他引:0
虽然椭圆波导已经在卫星通信和雷达馈线等方面得到了应用,然而在已往文献中,椭圆波导中没有一个模的场图是通过解析方法绘出的。本文给出了两种不同偏心率的椭圆波导中cE01模的级数解析表示式,并绘出了它们的场图。本文求解矢量场的方法是严格的和标准的。这个模的电场和磁场线确实和Xhu绘出的不同,他的场线是错误的。 相似文献
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脊加载椭圆波导传输特性的矢量有限元法分析 总被引:1,自引:0,他引:1
采用矢量有限元法对脊加载椭圆波导的传输特性进行了分析,编程计算了圆形脊、梯形脊和三角形脊分别加载在椭圆短轴和长轴上波导的截止频率.结果表明:脊加栽在椭圆长轴上,大大减小了单模带宽,因此这种结构可作为有效的脊带宽滤波器. 相似文献
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采用在椭圆柱坐标系中分离变量的方法,得到了填充多层介质共焦椭圆同轴线模式特征方程.研究表明:当椭圆退化为圆时,利用角向和径向马修函数的渐进关系,可得到填充多层介质的圆形同轴线的模式特征方程,由此可见,圆形同轴线可看作椭圆形同轴线的特例;当椭圆同轴线内导体半长轴大小为零时,则椭圆同轴线就变成椭圆波导,同样的方法,可得到填充多层介质的椭圆波导模式特征方程.当填充一层介质时,得到了椭圆同轴线和椭圆波导的模式特征方程,结果和相关文献所得结果相同.作为示例,对填充一层介质和两层介质的椭圆同轴线中一些模式色散特性进行了数值计算,分析了椭圆同轴线中介质参数的变化以及椭圆同轴结构的变化等对其传播特性的影响. 相似文献
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椭圆光波导解析解及第一个高阶模的截止频率研究 总被引:8,自引:1,他引:7
本文对椭圆光波导进行了严格的求解,得到了模场的精确解析解,导出了模式特征方程,并且证明了圆光波导仅是椭圆光波导的一个特例。文中还对第一个高阶模的特征方程进行一数值求解,得出不同椭圆度下的有效折射率与归一化频率的关系曲线及第一个高阶模的归一2化截止频率随椭圆比的变化。 相似文献
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Overmoded elliptical waveguide systems are shown to provide considerable lower insertion loss compared with standard types using the frequency band with exclusive TEc11 fundamental mode propagation. The considerations for the overmoded waveguide operation are outlined. A novel transition design based on transformer steps with curved cross sections and containing means for higher order mode control is established for interfacing the oversized elliptical cross section with the standard rectangular waveguide ports. The accurate determination of the transition structure maintaining high performance demands is obtained by a suitable computer-aided-design procedure. The overmoded waveguide approach, including the transition design, is proven by computed and experimental results for a millimeter-wave design 相似文献
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《Microwave Theory and Techniques》1960,8(4):431-435
The power-voltage, power-current and voltage-current impedances for the elliptical waveguide for the fundamental mode (/sub e/H/sub 1/ mode) are obtained by two different methods. The first method consists of using the exact fields inside a perfectly conducting elliptical pipe. Numerical results were obtained by numerical integration of the integrals involving Mathieu functions by the Gaussian Quadratures method by a digital computer. In the second method approximate fields which satisfy the boundary conditions were used. By this approximate method, actual expressions for the impedances are obtained as a function of minor to major diameter ratio with no need of numerical integration. The actual expressions for the impedance obtained by the approximate method give the impedance for elliptical waveguide within six per cent. On the basis of comparison with the exact numerical solution the expressions for the approximate impedance give the impedance of elliptical waveguide within three per cent if they are scaled by 1.03. 相似文献
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S. A. Manenkov 《Journal of Communications Technology and Electronics》2018,63(6):512-520
The problem of calculation of eigenmode characteristics is considered for 3D open dielectric waveguides and waveguides with the anisotropic impedance boundary condition. An efficient algorithm is proposed for finding eigenmodes of waveguides having different cross-sections. It is based on the solution of the auxiliary problem of diffraction of the field of a filamentous source located inside the waveguide. The method is tested using weakly directing dielectric waveguides having circular and elliptical sections and a waveguide with the two-sheeted section. The results of calculation of dielectric waveguides obtained with the help of the proposed method, the method of finite elements, and the method of the integral equation over the waveguide section are compared. The circular and elliptical waveguides and the waveguide having a two-sheeted section with an anisotropic impedance are also investigated. The calculation results are compared with the results obtained with the use of the method of separation of variables and the Galerkin method. 相似文献