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  傳播矢量就可以定義入射的角度，你只需要根據你的入射角算出其在xyz方向上的分量填入即可，電場矢量的設置也就代表了你的平面波入射場強
  我覺得場強信息里就已經含有頻率的相關信息了，不知道我的理解對不

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  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.
  

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  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.

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  我先設置E-field vector，設置z=sina, y=cosa, x=o,入射角應該為90-a，但是設置不了，前面的傳輸參數應該（我的理解是波的傳輸方向）和電場矢量垂直。

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  波的傳播方向，e，h三個矢量成右手原則
  設置不成功，可能是你的表達式書寫有錯誤，必須滿足cst的格式才可以

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  謝謝，電場矢量跟波長有什么關系不，我看一個參考文獻，如果對傳輸方向設置了角度應該會使平面波的平面有個角度變化，但是，文獻的圖如下，有可能會是這樣一個模型嗎？

  
  model.JPG

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  電場矢量是歸一化的值好像與波長沒有關系。書寫應該沒有錯誤，我都把角度除以了360，如果格式錯誤，好像會提示

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  球面波在距離源很遠處可以認為是均勻的平面波，你問的是否和波長有關系，我還真不是特別清楚，從軟件上看，根本沒有這個選項設置，個人覺得應該和那個沒什么關系，軟件只是模擬一種平面波入射的狀態，主要是傳播方向和E場矢量，而且是歸一化的場矢量即可，所以我覺得可以不用考慮你說的波長問題，直接模擬

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  好專業，學習一下。

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  直接輸入數值試試看

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  the computational domain is rectangular with dimensions Lx(500-2000nm),Ly(500-2000nm)Lz(650-4000nm)
  這個東西哪里有設置嗎？
  the dielectric objects were meshed at λ/10, while the plasmonic objects were meshed at  λ/30.
  這個都與波長有關，我在哪里設置��？

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  在mesh屬性里設置

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  屬性里面沒有看到對不同材料的設置。計算區域也沒有看見有選擇的

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  設置來自這篇文章，但是我還是不知道該在哪里設置，幫我看看！

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

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  設置來自這篇文章，但是我還是不知道該在哪里設置，幫我看看！ 文章第二頁，2，the FDTD model and simulations里面有模型和描述，對于設置不同材料的mesh density和computatioal domain，我一直都沒有找到地方。

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  Thank you！

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  太感謝你了，我的模型能運行了，計算時間很長，我還必須等到明天才有結果。希望一切結果都很好，也希望你天天開心。

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  文獻中的Fig2歸一化的電場平方值的分布情況是怎么得到的？用monitor還是probe？

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  通過添加探針可以觀測空間某點的電磁場，畫一條曲線，然后在后處理里面可以畫出該曲線上的場分布了

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  想賺金幣，咋弄啊  

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