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圆柱体上爬行波场分析及电磁兼容性设计应用 总被引:1,自引:0,他引:1
航空器上天线间辐射干扰问题的解决是系统正常通讯的保证。文章针对各种航空器的典型结构模型-圆柱体进行研究,应用几何绕射理论分析了圆柱体上爬行波场的分布规律,包括固定收发天线位置,频率变化时爬行波场分布规律和固定天线工作频率改变收发天线相地位置时场的分布规律,所得结论为解决航空器上天线系统空间布局的电磁兼容问题提供了设计依据,也为定量地预测天线间隔离度提供了有效手段。 相似文献
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目的计算并分析机载短波天线激励机身表面近场的分布.方法用B样条方法进行飞机的整体计算机建模,并模拟其机载的短波天线,用时域有限差分法完成短波天线激励机身表面近场的分析计算.结果得到了位于机身表面样点的近场分布,以曲线及飞机轴向纵剖面的场分布灰度图的形式表示.结论在这种建模方法下,分析所得结果符合机载天线理论,它可为机载短波天线阻抗特性、远场方向图的研究,以及短波通信设备对其它机载电子设备干扰问题的分析提供基础及依据,这种研究对飞机的电磁兼容分析和设计有重要意义. 相似文献
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As a lately developed technique for FDTD, R-FDTD (reduced-FDTD) algorithm is complicated for dealing with the problem of excitation setting. In order to get rid of such difficulty, two simple techniques are proposed. One technique is to classify field points into two types according to the value of electric divergence equa-tion. The other technique is subregion connection. The corresponding modified R-FDTD can not only inherit the memory-efficient character, but also eliminate the complexity aroused by the existence of excitation and conduc-tors. Simulation results are compared between those obtained from traditional FDTD and those from R-FDTD.Good agreement is observed. 相似文献
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Aim To analyze the transient speciality of nonlinear,
anisotropic, AC+DC coupling electric field, and to compare the withstand-voltage strength
of different insulation structures. Methods The transient process of
polarity reversal is analyzed, considering the anisotropic property of oil-immersed
press-board, a new finite element model based on Galerkin method is presented and
verified. The model developed is applied to calculate the electric field distribution in
four typical winding end structures of the converter transformer. Results
The whole-ring structure possesses the best insulation characteristics. Conclusion
By introducing reasonable insulation components, insulation strength with the
same surrounding sizes can be improved more than 30%. 相似文献
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从圆柱坐标系下麦克斯韦方程的时域有限差分式和特征解出发 ,引入了二维和三维圆柱坐标系下网格波阻抗 (MWI) .结合完全匹配吸收层 (PML)概念 ,推导出了二维圆柱坐标系下的MWI PWL吸收边界条件算法 .通过数值实验 ,研究了圆柱坐标系下网格波阻抗的正确性和它在圆柱坐标系下时域有限差分法 (FDTD)中的应用 .计算结果证明 ,当采用非均匀圆柱坐标系下FDTD法计算时 ,圆柱坐标系下网格波阻抗可以较准确地计算由于网格尺寸不同造成的数值反射误差 .同时 ,网格波阻抗也为确定网格尺寸容许可变的范围提供了理论标准 .二维圆柱坐标系下的MWI PML是一种简单、低反射的吸收边界条件 ,与Teixeira的完全匹配吸收层相比 ,其引起的数值反射误差增加不大但更易于实现 . 相似文献