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本文给出了螺旋-圆柱波导系统的特征方程,首次求得了此结构的复根模,推导出实根模,虚根模和复根模相互之间的分界条件,并给出了一些特征值曲线,最后,利用特征方程近似计算了一个螺旋-圆锥喇叭天线的远场辐射方向图,数值结果与实验进行了很好的比较。 相似文献
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沈忠祥 《红外与毫米波学报》1992,11(6):441-447
利用基于Bessel函数加法定理的坐标变换,获得了关于回旋媒质偏心加载圆波导中传播常数的特征方程.文中给出了回旋介质棒偏心加载圆波导时的色散特性曲线,并讨论了传播常数随各参数的变化. 相似文献
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黄志洵 《光纤与电缆及其应用技术》1994,(2):8-15
本文对表面波导系统的一种基本形式即单线传输线作系统性分析。论述了两种单线表面波波导,即Sommerfeld线和Goubau线。讨论了特征方程,工作性能,应用方法,以及实用时应当注意的若干问题。 相似文献
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本文给出了普适于任意阱数的方波折射率分布的多量子阶光波导的模场分布函数和特征方程,并以GaAs/AlGaAs多量子阱光波导为例分析讨论了波导结构参量及折射率分布对其传输特性的影响. 相似文献
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本文对圆形-矩形双槽波导结构进行了进一步的讨论,推导出了该结构在二级近似条件下的特征方程,提高了分析精度。 相似文献
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孙士乾 《电气电子教学学报》1987,(3)
自由离散系统的状态方程为:X(K+1)=AX(K),初值为X(0)(1)其中A为n×n阶常矩阵,X(0)为n阶矢量利用递推公式立即得到:X(K)=A~KX(0)(2)上式中含A~K,对于X(K)变化的性质不够明确。现利用特征值的方法,在参考书目1中讨论了A阵的特征值互不相等的情况。本文讨论有相同特征值的情况。1.A阵的特征值互不相等时:设特征方程为|A-λ1|=0=(λ-λ_1)(λ-λ_2)…(λ-λ_n), 相似文献
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提出了用于回肇磁控管的一种新型多波导结构,即扇形波导-隙缝结构,给出了它的特征方程和储能表达式,进行了大讯号计算,得到了几何尺寸与储能及效率的关系曲线,为这种结构的设计提供了依据。 相似文献
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The term "insertion loss" has become such a popular one and is applied to so many different concepts that it is becoming unsuitable for precise use. Certain other concepts connected with insertion loss such as attenuation and mismatch loss, are in need of clarification. A logical set of definitions and equations are presented as a suggested approach to more precise terminology. The effect of complex characteristic impedance on these equations is given in an Appendix. Specific suggestions are given for changes in the usage of terms, which if acceptable and adopted would improve the situation. 相似文献
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空间目标的红外辐射特性是对空间目标进行探测与识别的重要依据.首先分析了空间目标与外界环境的热交换关系,确定了目标表面的边界条件,推导出边界单元的有限差分形式,针对空间目标的遮挡问题.开展了判断方法的讨论,为准确计算目标的表面温度场奠定了基础.其次利用有限差分法求解其导热微分方程,获得了目标表面温度场分布特性;将总红外辐射分解为自发辐射和反射辐射两部分,分别给出了计算自发辐射强度和反射辐射强度的计算式.最后以某空间目标为例,利用数值方法计算表面温度场,并在此基础上计算了红外辐射强度的空间分布,对计算结果进行了分析. 相似文献
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汪建 《电气电子教学学报》2007,29(1):39-43
基尔霍夫定律和元件特性是电路分析的两个基本依据,支路方程是元件特性的具体体现形式.随着计算机技术在电路分析和电路设计中的广泛应用,用系统法建立电路方程这一内容在电路理论课程的教学中日显重要.正确地理解和列写矩阵形式的含受控源支路的特性方程是学习系统法的重点和难点之一.本文就电路中典型支路特性方程的讲解进行了较为深入的讨论,对矩阵形式支路方程的列写方法和步骤以及对方程中各项含义的正确理解进行了详细的论述. 相似文献
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The pyramidal horn exhibits a normal monotonically increasing gain versus frequency characteristic, only when its axial length is more than a certain minimum value for given aperture dimensions. In this letter, approximate equations are derived for estimating this minimum axial length 相似文献
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This paper deals with the analysis of the transient and steady-state processes in parallel inverters. A set of difference equations, describing the currents and voltages during transient and steady state is obtained and solved. The solution is found in closed form. The roots of the characteristic equations are examined and possible types of transients are discussed. Theoretical and experimental results both for transient and steady-state conditions are compared and satisfactory agreements are found. 相似文献
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A flanged parallel-plate waveguide is used for the detection of a two-dimensional surface crack on a metal plate. The Fourier transform and the mode-matching technique are used to obtain simultaneous equations, which are solved to represent the crack characteristic signal. The characteristics of the crack, such as position, Width, depth, and material in the crack, are discussed in terms of the crack characteristic signal 相似文献
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在辛体系下利用精细积分对矩形波导纵向排列介质层PBG结构进行了分析,并对滤波器进行了优化设计.采用棱单元对波导的横截面进行离散,然后导向哈密顿体系,运用基于黎卡提微分方程的精细积分求出一段介质层和一段空气层的出口刚度阵,再利用区段合并以对问题求解.在此基础上采用序列线性规划法对模型进行求解,得到了滤波性能最优的设计参数.算例表明本文方法具有精确、高效的优点. 相似文献
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Jaewang Yu Il-Bum Kwon Kyunghwan Oh 《Lightwave Technology, Journal of》2003,21(8):1779-1786
We report a thorough analysis on the Brillouin frequency shift as a function of geometrical parameters in a silica optical fiber consisting of triple-layered structure, GeO/sub 2/-doped core, P/sub 2/O/sub 5/, and F co-doped inner cladding, and pure silica outer cladding. General characteristic equations for the Brillouin frequency shift were analytically derived and analyzed for various fiber parameters. In experiments, three-layered optical fibers were fabricated and their Brillouin frequency shifts were measured in the wavelength region of 1.55 /spl mu/m by a pump-probe technique. The longitudinal acoustic velocity in each layer was found significantly affected by the thermal stress as well as the dopant concentrations. We confirmed both in theory and experiment that the inner cladding of a three-layered optical fiber does provide a new degree of freedom in precise control of the Brillouin frequency shift. 相似文献