微波EDA (www.mweda.com) 网友回复：

• 网友回复

  传播矢量就可以定义入射的角度，你只需要根据你的入射角算出其在xyz方向上的分量填入即可，电场矢量的设置也就代表了你的平面波入射场强
  我觉得场强信息里就已经含有频率的相关信息了，不知道我的理解对不

• 网友回复

  Plane Wave OverviewThe plane wave excitation source provides you the opportunity to simulate an incident wave from a source, located a large distance from the observed object. In combination with farfield monitors, the radar cross section (RCS) of a scatterer may be calculated.Please note that the input signal of an excited plane wave is normalized due to the user-defined value of the electric field vector (unit: V/m).When exciting with a plane wave, several conditions must be satisfied, which will be discussed in the following section.Boundaries and background material
  When exciting with a plane wave, several conditions must be satisfied. First, open boundary conditions must be defined at the direction of incidence.
  In the picture below, a plane wave is passing the calculation domain in the (1, 1, 1) direction. At a minimum, the boundaries at xmin, ymin and zmin must be defined as open boundaries (for an undisturbed propagation, xmax, ymax and zmax must be open as well).
  

  When using a plane wave source, other excitation ports must not be located on boundary conditions. Moreover the surrounding space should consist of a homogenous material distribution. This implies that the background material is set to a normal, not a conducting material. Unlike the other excitation sources, a plane wave can only be driven by a Gaussian pulse.
  Decoupling plane
  If the calculation domain is divided by a metallic plane (which needs to be parallel to a boundary condition), it is necessary to define a decoupling plane at the boundary of the metallic plane. This is possible either by an automatic detection or by user settings in the Plane Wave dialog.
  The picture shows a plane wave hitting a metallic plane with three slots. The detected decoupling plane is marked with a pink frame. In front of the plane, a standing wave field pattern has been established; behind the plane, a typical interference pattern can be seen.
  

  Polarization
  It is possible to define three different kinds of polarizations for a plane wave excitation: linear, circular or elliptical. For linear polarization, one electric field vector exists for the excitation plane with a fixed direction. This electric field vector changes its magnitude according to the used excitation signal. A linear polarization is displayed as red plane with a green electric field vector and a blue magnetic field vector. The visualization of the linear plane wave excitation is displayed in the picture below.
  

  For circular or elliptical polarization, two electric field vectors exist in the excitation plane perpendicular to each other. Each of these two vectors define one linear polarized plane wave. If these two linearly polarized plane waves are excited simultaneously, the resulting plane wave is elliptically polarized. Please note that circular polarization and linear polarization are special cases that may result from the definition of an elliptical polarization.
  For a circular or elliptical polarization, the two electric field vectors are excited simultaneously according to the excitation signal with a certain time delay. This time delay is calculated for a given reference frequency and a phase shift between the two electric field vectors. In addition, the magnitude of the two electric field vectors may be different. The axial ratio defines the ratio of the magnitudes between the defined (first, primary) electric field vector and the perpendicular second vector.
  The special case of a linearly polarized plane wave excitation is obtained if the phase shift between the two electric field vectors is 0 or 180 degrees. Please note that the phase shift is always related to the given phase reference frequency.
  For a circular polarization the axial ratio is always 1 as well as the phase shift is always +90 or –90 degrees. Therefore, only two possible configurations exist for a circular polarization: left and right circular polarization. The circular polarization is displayed as a green circular arc starting at the primary electric field vector (gray color) using an arrow  to indicate whether left or right circular polarization is used. The visualization of a left and right circular  plane wave excitation is displayed in the two pictures below.
  

  Left Circular Polarization (LCP)	Right Circular Polarization (RCP)

  
  If the phase shift differs from +90 or –90 degrees or the axial ratio is not equal to 1, the polarization is elliptical. Elliptical polarization is displayed similar to circular polarization. An elliptical arc denotes the sense of the polarization and its magnitude in the plane regarding the course of time at the given reference frequency. The arc starts at the resulting electrical field vector at the time when the primary electric field vector (i.e., the field vector of the first linear plane wave) is at maximum. This resulting field vector is displayed as a green arrow if there is a significant difference to the primary field vector (gray).
  If the phase shift at the reference frequency is positive, the time when the primary field vector reaches its maximum equals a phase of 0 degrees for an electric field monitor defined at the reference frequency. If the phase shift is negative, there will be an additional phase offset between the fields recorded by an electric field monitor at the reference frequency and the green arrow will be visualized when the plane wave definition is visualized.
  The visualization of three different elliptical plane wave excitations is displayed in the three pictures below.
  

  Axial ratio: 0.6667 Phase shift: 90 degrees	Axial ratio: 1 Phase shift: 60 degrees	Axial ratio: 0.6667 Phase shift: 60 degrees

  
  The following picture shows the spatial field distribution of a plane wave excitation with right circular polarization for a fixed time. Please note that for a fixed time, the spatial rotation of the field along the propagation direction is in the left direction for a right circular polarized plane wave.
  

• 网友回复

  Within this dialog, you may define a plane wave excitation source. Unlike discrete ports or waveguide ports, no S-parameters will be calculated. Instead, the stimulation amplitude (unit is V/m) is recorded. To obtain further information, you might specify probes or different types of field monitors. Combined with farfield monitors, the plane wave source can be used to compute the radar cross section (RCS).Polarization frame
  Here, you may enter the polarization of the plane wave and polarization specific settings. For more information on the different polarization types, please see the Plane Wave Overview.
  Linear / Circular / Elliptical: Select here the type of plane wave excitation polarization.
  Ref. frequency: If the selected type is circular or elliptical, enter here the reference frequency for the plane wave excitation. This field only applies to elliptical and circular polarized plane wave excitations.
  Phase Difference: Enter here the phase difference between the two excitation vectors for elliptical polarized plane waves. This field only applies to elliptical polarized plane wave excitations.
  Left / Right: Select here between left circular polarized or right circular polarized plane wave excitation. These settings only apply to circular polarized plane wave excitations. The respective radio buttons are only visible if a circular polarization is selected.
  Axial ratio: Defines the ratio between the  amplitudes of the two electric field vectors used for elliptical polarization. This field only applies to elliptical polarized plane wave excitations.
  Propagation normal frame
  X/Y/Z: Here you can specify the propagation vector by entering valid expressions for the X/Y/Z component.
  Electric field vector frame
  X/Y/Z: Specify the electric field vector components in V/m. The electric field vector must be orthogonal to the propagation normal.
  Please note that the input signal of an excited plane wave is normalized due to the defined absolute value of the electric field vector.
  

  The definition of the plane wave is visualized by a red plane. Colored arrows indicate the propagation direction as well as the electric and magnetic field vectors.	Here the electric field vector of a plane wave is hitting a metallic sphere. Correspondent to the picture on the left side the plane wave is excited with an electric field vector in z-direction and a propagation normal (1,1,0).

  Decoupling plane frame
  If a structure contains metallic walls dividing the calculation domain into two separate parts, it is necessary to consider a decoupling plane in the plane wave calculation. Note that this decoupling plane needs to be parallel to the calculation domain‘s boundaries (see also: Plane Wave Overview ).
  Automatic detection: The selection of this checkbox will automatically detect possible metallic walls and consequently activate the correspondent decoupling plane. This detection procedure only recognize a complete metallic wall with no discontinuity at the boundary of the calculation domain. If the decoupling plane was not found, you can define one by yourself using the input fields below.
  Use decoupling plane: This checkbox is only available if the automatic detection is deselected. Activate here a user-defined decoupling plane defining the following input fields.
  Position: Determine the longitudinal location of the decoupling plane by entering valid expressions . If the metal wall has a finite thickness specify the walls boundary coordinate, where wave will be reflected.
  Plane normal: Select a normal direction for the decoupling plane. Decoupling planes must be parallel to the calculation domain‘s boundaries, so you can choose between X, Y or Z.
  OK
  Accepts your settings and leaves the dialog box.

• 网友回复

  我先设置E-field vector，设置z=sina, y=cosa, x=o,入射角应该为90-a，但是设置不了，前面的传输参数应该（我的理解是波的传输方向）和电场矢量垂直。

• 网友回复

  波的传播方向，e，h三个矢量成右手原则
  设置不成功，可能是你的表达式书写有错误，必须满足cst的格式才可以

• 网友回复

  谢谢，电场矢量跟波长有什么关系不，我看一个参考文献，如果对传输方向设置了角度应该会使平面波的平面有个角度变化，但是，文献的图如下，有可能会是这样一个模型吗？

  
  model.JPG

• 网友回复

  电场矢量是归一化的值好像与波长没有关系。书写应该没有错误，我都把角度除以了360，如果格式错误，好像会提示

• 网友回复

  球面波在距离源很远处可以认为是均匀的平面波，你问的是否和波长有关系，我还真不是特别清楚，从软件上看，根本没有这个选项设置，个人觉得应该和那个没什么关系，软件只是模拟一种平面波入射的状态，主要是传播方向和E场矢量，而且是归一化的场矢量即可，所以我觉得可以不用考虑你说的波长问题，直接模拟

• 网友回复

  好专业，学习一下。

• 网友回复

  直接输入数值试试看

• 网友回复

  the computational domain is rectangular with dimensions Lx(500-2000nm),Ly(500-2000nm)Lz(650-4000nm)
  这个东西哪里有设置吗？
  the dielectric objects were meshed at λ/10, while the plasmonic objects were meshed at  λ/30.
  这个都与波长有关，我在哪里设置啊？

• 网友回复

  在mesh属性里设置

• 网友回复

  属性里面没有看到对不同材料的设置。计算区域也没有看见有选择的

• 网友回复

  设置来自这篇文章，但是我还是不知道该在哪里设置，帮我看看！

  Optical near-field distribution.pdf
  (2009-02-18 23:22:14, Size: 487 KB, Downloads: 5)

• 网友回复

  设置来自这篇文章，但是我还是不知道该在哪里设置，帮我看看！ 文章第二页，2，the FDTD model and simulations里面有模型和描述，对于设置不同材料的mesh density和computatioal domain，我一直都没有找到地方。

• 网友回复

  Thank you！

• 网友回复

  太感谢你了，我的模型能运行了，计算时间很长，我还必须等到明天才有结果。希望一切结果都很好，也希望你天天开心。

• 网友回复

  文献中的Fig2归一化的电场平方值的分布情况是怎么得到的？用monitor还是probe？

• 网友回复

  通过添加探针可以观测空间某点的电磁场，画一条曲线，然后在后处理里面可以画出该曲线上的场分布了

• 网友回复

  想赚金币，咋弄啊  

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