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详细介绍了谱域矩量法(SMOM)中V矩阵的快速求取,重点论述了改进的量子遗传算法与谱域矩量法的结合,并采用直接矩阵操作技术(DMM)实现对微带天线的优化设计.最后数值结果与商业软件(HFSS)结果的比较说明了算法的有效性. 相似文献
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外插脉冲响应(EIR)滤波器设计技术是一种低复杂度有限冲击响应(FIR)滤波器设计技术,而基于主成份分析(PCA)的EIR(PCA-EIR)滤波器设计技术是一种有效(算法执行简单,效果较好)的EIR滤波器设计技术.PCA-EIR技术通过对由原型FIR滤波器系数组成的系数矩阵采用PCA技术进行降维来近似合成原型FIR滤波器,以达到降低原型滤波器硬件执行复杂度的目的.本文提出了一种简单有效的改进型PCA-EIR技术,其基本思想是将系数矩阵的前若干列向量保持不变,对剩余部分列向量组成的矩阵采用PCA技术进行降维来合成原型FIR滤波器.所提出改进型PCA-EIR技术的算法执行复杂度与传统PCA-EIR技术相当,且在滤波器频率响应指标基本相等的前提下,改进型PCA-EIR技术节省3.5%-17.5%乘法器和25.6%-51.6%加法器,从而进一步降低了FIR滤波器的硬件执行复杂度. 相似文献
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本文针对体积分方程矩量法(VIE-MoM)分析三维非均匀介质电磁散射问题所导出的大型矩阵方程的求解问题, 基于多层快速极子技术(MLFMA)算法研究了快速近似迭代方法.提出了一种基于MLFMA分组方案对系数矩阵进行重组并提取强耦合元素的近场预条件器的构造方法,有效地提高了广义最小余量法(GMRES)的迭代收敛速度.提出了一种在迭代计算过程中的近似矩阵向量乘积方案,明显降低了单步计算过程中MLFMA远区耦合作用的计算时间.计算实例表明,采用本文的迭代加速技术可使计算速度提高3至5倍,有效地提高了VIE-MoM大型矩阵方程的迭代求解速度. 相似文献
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《中国无线电电子学文摘》1999,(6)
TN701,TN711 99060492开关电流神经网络/李黎明,何怡刚,吴杰(广州海军舰艇学院)11固体电子学研究与进展.一1 999,19(2)一149一156综述了开关电流神经网络实现问题,讨论了神经网络的两种模拟实现方法一一开关电容和开关电流技术的特点,给出了神经网络的开关电流技术实现的一些基本单元电路,指出了这种实现技术存在的问题及解决的办法.图4参12(许)TN701 99060493用埃米特式计算复功率/黄炳华(广西大学)11电路与系统学报.一1999,4(2)一45一52K端口网络的导纳矩阵Y=HG j HB,其中称H口为埃米特矩阵的第一形式,HB为埃米特矩阵的第二形式、文… 相似文献
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基于六面体的高阶叠层基函数,提出了一种新颖的构造预条件矩阵的方法.该方法基于叠层基函数特有的嵌套性质,利用特殊的编号策略,将由有限元方法导致的系数矩阵分成块矩阵的形式,最后由不完全LU分解(ILU)导出近似的预条件矩阵.结合该预条件技术,发展了一种叠层预条件-GMRES算法,并将该预条件算法用于加速三维腔体散射的矢量有限元/边界积分(FE-BI)矩阵方程的迭代求解,讨论了该预条件算法中块矩阵ILU分解截断门限Tdr对算法的影响. 相似文献
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Yetta 《激光与光电子学进展》2007,44(1):13-13
剑桥显示器科技(CDT)公司宣布一项在有机发光二极管(OLED)显示器技术上的重大进展:整体矩阵寻址(Total Matrix Addressing,TMA)技术.利用该技术可以制作大尺寸、高分辨率和性价比高的OLED显示器. 相似文献
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This paper presents an integral equation based scheme to analyze scattering from inhomogeneous bodies with anisotropic electromagnetic properties. Both the permittivity and permeability are assumed to be generalized tensors. Requisite integral equations are derived using volume equivalence theorem with the electric and magnetic flux densities being the unknown quantities. Matrix equations are derived by discretizing these unknowns using three dimensional Rao-Wilton-Glisson basis functions. Reduction of the integral equation to a corresponding matrix equation is considerably more involved due to the presence of anisotropy and the use of vector basis function; methods for evaluation of the integrals involved in the construction of this matrix is elucidated in detail. The method of moments technique is augmented with the fast multipole method and a compression scheme. The latter two enable large scale analysis. Finally, several numerical results are presented and compared against analytical solutions to validate the proposed scheme. An appendix provides analytical derivations for the formulae that are used to validate numerical method, and the necessary formulae that extends the approach presented herein to the analysis of scattering bianisotropic bodies. 相似文献
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文中通过求解薛定谔方程得到抛物型形量子阱的变换矩阵与透射系数。利用这一结果计算透射系数可以达到任意高的精度,最后,讨论了结构变化对抛物型量子阱的共振隧穿的影响。 相似文献
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抛物方程方法的亚网格模型及其应用研究 总被引:1,自引:0,他引:1
该文在抛物方程非均匀网格技术的基础上,提出了抛物方程方法的亚网格模型,并给出了该亚网格模型的具体构建方法,以快速准确地求解大尺度复杂电磁环境中存在关键目标的电波传播问题。通过对存在强散射体的复杂电磁环境中电磁波的分布特性进行模拟,探讨了抛物方程亚网格技术的高效性。结果表明:与细网格相比,亚网格技术使得抛物方程的计算速度提升了4.57倍,网格空间数下降了86.64%,且较非均匀网格具有更高的计算精度。可见,抛物方程的亚网格模型能够极大地提升抛物方程的仿真效率。 相似文献
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The two-dimensional (2-D) parabolic equation (PE) is widely used for making radiowave propagation predictions in the troposphere. The effects of transverse terrain gradients, propagation around the sides of obstacles, and scattering from large obstacles to the side of the great circle path are not modeled, leading to prediction errors in many situations. In this paper, these errors are addressed by extending the 2-D PE to three dimensions. This changes the matrix form of the PE making it difficult to solve. A novel iterative solver technique, which is highly efficient and guaranteed to converge, is presented. In order to confine the domain of computation, a three-dimensional (3-D) rectangular box is placed around the region of interest. A new second-order nonreflecting boundary condition is imposed on the surface of this box and its angular validity is established. The boundary condition is shown to keep unwanted fictitious reflections to an acceptable level in the domain of interest. The terrain boundary conditions for this 3-D PE method are developed and an original technique for incorporating them into the matrix form of the iterative solver is described. This is done using the concept of virtual field points below the ground. The prediction accuracy of the 3-D PE in comparison to the 2-D PE is tested both against indoor scaled frequency measurements and very high frequency (VHF) field trials 相似文献
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Two problems in the self-consistent, electrothermal co-simulation of nanoscale devices, are discussed. It is shown that the construction of dynamic compact thermal models for nanoscale devices, based on solution of the hyperbolic (wavelike) heat transport equation, can follow essentially the same approach as the authors' analytical thermal impedance matrix method for the parabolic (diffusive) equation. The physicality of the hyperbolic equation is discussed in the light of calculated results. The analytical impedance matrix method for the time-independent case is employed in a thermally self-consistent device Monte Carlo simulation, illustrating the potential for detailed study of nanoscale electrothermal effects. 相似文献
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An integral equation and method of moments (MM) solution are presented for the two-dimensional (2-D) problem of transverse magnetic (TM) scattering by an impedance-sheet extension of a perfectly conducting parabolic cylinder. An integral equation is formulated for a dielectric cylinder of general cross section in the presence of a perfectly conducting parabolic cylinder. It is then shown that the solution for a general dielectric cylinder considerably simplifies for the special case of TM scattering by a thin multilayered dielectric strip that can be represented as an impedance sheet. The solution is termed an MM/Green's function solution, where the unknowns in the integral equation are the electric surface currents flowing in the impedance sheet; the presence of the parabolic cylinder is accounted for by including its Green's function in the kernel of the integral equation. The MM solution is briefly reviewed, and expressions for the elements in the matrix equation and the scattered fields are given. Sample numerical results are provided 相似文献