共查询到18条相似文献,搜索用时 171 毫秒
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基于电流的矩量法(method of moments,MoM)和物理光学法(physical optics,PO)的混合算法是目前求解电中尺度和多尺度目标电磁散射和辐射的主要方法,在计算MoM区和PO区的耦合作用时需要对PO区域进行亮区判断.传统纯CPU亮区判断方法时间复杂度为O(N2),时间消耗随着面片数量N增加而急剧增大.文中通过GPU渲染功能及对深度缓冲区(zbuffer)的利用,对PO亮区判断过程进行加速,亮区消耗时间与面片数量无直接联系,在面片数量达到105数量级以上加速优势明显.将加速的MoM-PO混合方法应用于复杂目标与粗糙面的组合情况,对比多层快速多级子(multi level fastmultipole method,MLFMA)方法,相比于纯PO方法,获得较高的精度.相比于单一算法,混合算法有明显优势. 相似文献
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基于UV技术加速的矩量法/物理光学混合算法(UV/MoM-PO),研究了电大尺寸载体对位于其附近的阵列天线性能的影响.在UV/MoM-PO算法中,载体被设置为PO区域,阵列天线被设置为MoM区域.PO区域采用三角面片剖分,并用RWG基函数展开,MoM区域则用线段剖分,并用分段线性基函数展开.根据与MoM区域的远近,将PO区域的单元分组,其中每个小组与MoM区域的相互作用矩阵采用UV分解技术快速得到.给出了两个具体的算例,并与多层快速多极子(MLFMM)的结果进行了比较,表明本文的算法有较好的计算精度. 相似文献
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利用电磁混合算法对复杂目标进行电磁精确建模仿真,以获得真实目标较为准确的雷达高分辨像信息,对未来高分辨雷达实现目标探测与自动识别有着重要的意义.对于电大尺寸复杂目标电磁仿真计算,高频近似方法和低频数值方法各有其优势和局限性,如能结合两者的优点来解决计算中的精度和速度问题,将对建立高分辨目标特征库有着重要的帮助.本文以低频矩量法(MoM)和高频物理光学法(PO)混合为例, 提出了基于MoM-PO混合算法来精确求解电大尺寸目标的高分辨电磁散射特性,有效地提高了计算精度, 改善了计算速度, 为快速有效地解决复杂电大尺寸目标的高分辨特征提取提供了良好的途径.通过对典型目标和实际复杂目标实例的仿真计算,提取高分辨特征结果验证了该方法的有效性和实用性. 相似文献
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提出了一种基于矩量法(MoM)结合多层快速多极子(MLFMA)和自适应交叉近似(ACA)算法计算目标电磁特性的算法,该算法实现了对电大尺寸复合目标散射计算的加速和内存的降低。对于目标自作用的近场区域,多层快速多极子加速矩量法中的矩阵矢量乘运算,降低了计算的存储和复杂度;对于远场区域,根据阻抗矩阵的低秩特性,采用ACA对其压缩,加速矩阵的填充。矩阵填充按照树形结构划分的单元块间的相互作用依次进行存储,对每一块与块之间的求解采用ACA算法,对矩阵做压缩处理。提出的基于ACA的混合算法能够对2个目标耦合作用的阻抗矩阵进行压缩,缩短矩阵的填充时间并降低内存需求,同时也能够减少迭代求解过程中矩阵向量的计算时间,从而极大缩短电磁散射计算的总时间。数值仿真实验表明该算法比传统方法计算更高效,且计算精确度保持一致。 相似文献
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采用矩量法(MoM)计算电大尺寸的复合目标的电磁散射。为了能够高效快速地计算电大尺寸三维复合目标的电磁散射,提出一种新的混合方法,将自适应交叉近似(ACA)算法和多层快速多级子(MLFMA)算法相结合,共同加速矩量法的计算。其中,MLFMA用于加速目标与自身的作用,ACA用于加速目标与其他目标的相互作用。提出的混合算法在计算复合目标电磁散射时,可降低运算存储,缩短阻抗矩阵填充时间,并且能够加快矩阵矢量乘,且不影响计算精确度。数值算例表明,所提快速算法能够在保证电磁散射计算精确度前提下,比传统方法更高效。 相似文献
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本文实现了一种使用物理光学(PO)计算雷达散射截面的算法。目标模型用非均匀有理B样条(NURBS)曲面建立,并使用等参数等弦长方法剖分为N个四边形面元。在剖分面元上,使用Gordon方法将物理光学积分转化为闭合区域线积分。整个算法在在保持计算精度的前提下有较高的计算速度。 相似文献
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Ming Chen Yu Zhang Xun-Wang Zhao Chang-Hong Liang 《Antennas and Propagation, IEEE Transactions on》2007,55(2):407-413
The hybrid method of moments and physical-optics (MoM-PO) approach is used to calculate the radiation pattern of antenna around arbitrarily shaped structure. The structure is modeled with Non-uniform rational B-spline (NURBS) surfaces. The hybrid MoM-PO approach is implemented by modifying the impedance matrix of the MoM region with PO. Formula for the scattered PO field is deduced for cases of antenna located around NURBS surface. The stationary phase method (SPM) is applied for the integral of the induced current in the PO region. Results obtained from this method and from MoM-PO approach based on triangle facet model agree well while the former is more efficient in execution time 相似文献
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Higher order hybrid method of moments-physical optics modeling technique for radiation and scattering from large perfectly conducting surfaces 总被引:3,自引:0,他引:3
An efficient and accurate higher order, large-domain hybrid computational technique based on the method of moments (MoM) and physical optics (PO) is proposed for analysis of large antennas and scatterers composed of perfectly conducting surfaces of arbitrary shapes. The technique utilizes large generalized curvilinear quadrilaterals of arbitrary geometrical orders in both the MoM and PO regions. It employs higher order divergence-conforming hierarchical polynomial basis functions in the context of the Galerkin method in the MoM region and higher order divergence-conforming interpolatory Chebyshev-type polynomial basis functions in conjunction with a point-matching method in the PO region. The results obtained by the higher order MoM-PO are validated against the results of the full MoM analysis in three characteristic realistic examples. The truly higher order and large-domain nature of the technique in both MoM and PO regions enables a very substantial reduction in the number of unknowns and increase in accuracy and efficiency when compared to the low-order, small-domain MoM-PO solutions. The PO part of the proposed technique, on the other hand, allows for a dramatic reduction in the computation time and memory with respect to the pure MoM higher order technique, which greatly extends the practicality of the higher order MoM with a smooth transition between low- and high-frequency applications. 相似文献
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本文采用基于非均匀有理B样条(NURBS,Non-Uniform Rational Bezier Spline)曲面建模技术的物理光学方法结合矩量法(Method of Moments-Physical Optics)分析位于电大尺寸平台附近天线的辐射方向图.文章推导了基于有理贝齐尔曲面的物理光学散射场计算公式.采用驻相法计算有理贝齐尔曲面上的物理光学感应电流积分.利用物理光学散射场迭代矩量法区域的电压矩阵.通过与传统平面片建模的物理光学方法的计算结果对比,说明本文方法的有效性和优点. 相似文献
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任意形状电大散射体附近天线受扰方向图的快速分析 总被引:1,自引:0,他引:1
该文采用基于非均匀有理B样条曲面(NURBS)建模的物理光学方法结合矩量法(MoM-PO)分析任意形状电大散射体附近天线的受扰方向图。采用插值驻相点技术加快了方向图的计算速度。文章推导了基于有理贝齐尔曲面的物理光学散射场计算公式,采用驻相法(SPM)计算有理贝齐尔曲面上的物理光学感应电流积分从而得到物理光学散射场,并利用物理光学散射场迭代矩量法区域的电压矩阵。通过与传统平面片建模的物理光学方法的计算结果对比,说明该文方法的有效性和计算速度快的优点。 相似文献
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Coupled TDIE-PO method for transient scattering from electrically large conducting objects 总被引:1,自引:0,他引:1
An efficient hybrid method based on the time domain integral equation (TDIE) coupled with physical optics (PO) is proposed for the transient scattering from electrically large conducting objects. The computational complexity of the proposed hybrid method is drastically reduced compared with full TDIE, and the accuracy is improved compared with only PO. The numerical results demonstrate the validity and efficiency of the hybrid method. 相似文献
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An iterative current-based hybrid method for complex structures 总被引:6,自引:0,他引:6
This paper presents a general unified hybrid method for radiation and scattering problems such as antennas mounted on a large platform. The method uses a coupled electric-field integral equation (EFIE) and magnetic-field integral equation (MFIE) formulation, referred to as the hybrid EFIE-MFIE (HEM), in which the EFIE and MFIE are applied to geometrically distinct regions of an object. The HEM is capable of modeling arbitrary three-dimensional (3-D) metallic structures, including wires and both open and closed surfaces. We show that current-based hybrid techniques that utilize physical optics (PO) are an approximation of the HEM formulation. A numerical solution procedure is given that combines the moment method (EFIE) with an iterative Neumann series technique (MFIE). This permits one to effectively utilize the PO approximation when appropriate, and provides a general and systematic mechanism to correct the errors introduced by PO. Consequently, the HEM overcomes the inherent limitations of hybrid techniques which rely upon ansatz-based improvements of PO. The method is applied to the problem of radiation from objects that can be modeled using wires and metallic surfaces as fundamental elements. A representative example is given to demonstrate that the method can handle the difficult problem of a parasitic monopole located in the deep shadow region 相似文献