CST天线例子 - 图文

Results Plot Properties... [Farfield Plot] General

The farfield is represented by two components (E?,E?) at spherical coordinates Theta and Phi. The coordinates Theta and Phi relate to the cartesian coordinate system, as can be seen in the 3D plot below. See Farfield View for help on the possible selections in the navigation tree.

All plots are scaled logarithmic in dB but can be changed to linear in the Farfield Plot Special Settings dialog (use the Specials... -button). Plot type frame

Polar: Plots the farfield with one coordinate varying and one fixed as a polar plot. Underneath the plot, secondary coefficients such as frequency, main lobe magnitude and direction, 3dB-angular width and side lobe suppression, will be shown.

Cartesian: Plots the farfield with one coordinate varying and one fixed as a cartesian plot. You can get exact field values by using the option Axis Marker from the Results menu.

2D: Plots the farfield with both coordinates varying as a 2D plot with each point colored according to its field value (see the color bar below the plot). Additionally, you will get the exact field value by moving

the

mouse

on

the

demanded position in the plot. The value will be shown in the plot’s lower right corner.

3D: Plots the farfield with both coordinates varying as a 3D plot.

Vary / Angle step width frame

Theta / Phi, Azimuth / Elevation, Alpha / Epsilon or Vertical / Horizontal: Select here which coordinate you want to be variable in your plot. These radio buttons are only active if you have selected Plot Type Polar or Cartesian.

Phi / Theta, Elevation / Azimuth, Epsilon / Alpha or Horizontal / Vertical: The title of this entry depends on your selection in the Vary frame and on the selected coordinate system in the Coordinate system frame. If you have selected Theta to be variable, you will have to set the constant value for Phi here. Else enter the constant value for Theta. You can enter decimal fractions using your keyboard. This entry is only active if you have selected Plot Type Polar or Cartesian.

Theta Step / Phi Step, Azimuth / Elevation Step, Alpha / Epsilon Step, Vertical / Horizontal Step or Step: The title of this entry depends on your selection in the frames Vary, Plot Type and Coordinate system. You may enter the angular step size in degrees for your plot here. In addition, 2D and 3D plots allow the independent specification of theta step and phi step. Select Lock steps to enforce a common step width. Small step sizes will result in a long time to calculate your plot. For Plot Type Polar or Cartesian, first try a step size of 5. For Plot Type 2D or 3D, much more points have to be calculated; therefore, it is better to first set a step size of at least 15.

The smallest allowed step size is 0.01 degree for Polar or Cartesian and 0.25 degree for 2D or 3D. To enter step sizes <1, please use your keyboard. Only certain step sizes are allowed. Your input will be set to the closest smaller allowed value. Farfield and Structure view frame

These settings are only active if the 3D-plot type has been chosen. With these settings it is possible to plot the farfield and the structure at the same time. It is very helpful to realize the spatial relation between the main or side lopes and the modelled antenna.

Show structure: Enables to plot the structure into the 3D-farfield plot:

Structure transparent: Only active if \Use this option in cases the antenna obscures most of the farfield plot.

Farfield size slider: Only active if \plot without zooming the structure Color Ramp ...

Opens the Color Ramp dialog box allowing you to set your preferred color mapping for the 2D/3D farfield plots. Color by value

In case of plot type 3D, use color ramp to map plot values to colors. Use the Color Ramp dialog to modify the mapping. Draw step lines

In case of plot type 3D, draw black lines at each angular step. The step size can be set in the farfield plot dialog box. Step lines are not very useful in unzoomed plots with step sizes of 1 degree or below. Draw iso longitude / latitude lines

Activates iso lines for the longitude and latitude of the currently active coordinate system. These lines will be displayed together with farfield 3D plots. Plot range for polar angles 0..360 degree

This settings extends the plot range of the polar angle (theta, elevation, alpha) to the full circle. The plot range of the corresponding lateral angle (phi, azimuth, epsilon) is reduced accordingly, depending on the active plot type. Plot range –180..180 degree

Choose the plot range of the lateral angles (phi, azimuth, epsilon) symmetric about the origin. This setting is also applied to the polar angles if possible. Angular range frame

These settings restrict a 2D or 3D farfield plot to a specified angular range. Plot angular range only: Activates the phi and theta plot range. ThetaStart / ThetaEnd: Sets the displayed theta range. PhiStart / PhiEnd: Sets the displayed phi range.

Please note that both angular ranges always refer to spherical coordinates. Frequency / Time

Sets the desired plot frequency or the plot time. Select Set time to toggle between farfield calculation and transient field display. These settings are only available for broadband farfields. Save As Source

Use this button to save the farfield to a file which can be used for setting up a farfield source. The angular step size of the plot will be used as step size in the saved ASCII file .Therefore it is recommended to set the step size to a rather small value (e.g. 1 degree) to ensure high accuracy of the simulation where the farfield source is used.

Please use the Origin page to set the origin to the center of the antenna in. In case this page is not available please use the VBA object FarfieldArray to set the origin first and save the resulting farfield as source (Example Farfield Origin VBA).

This button is disabled for the plot types Cartesian and Polar Plot . OK

Stores the current settings and closes the dialog box. Depending on the new settings a new plot of the farfields will be calculated. The calculation can be aborted by pressing the Abort button. Apply

Stores the current settings leaving the Farfield Plot tab sheet opened. Depending on the new settings a new plot of the farfields will be calculated. The calculation can be aborted by pressing the Abort button. FF View / Preview

Use this button to switch between farfield view and coordinate system preview. The latter hides the farfield and just shows the structure in respect to the defined coordinate system. Abort

Aborts the current calculation. Note that the last plot has been deleted. You will have to calculate a new plot by making the appropriate settings and pressing the OK or Apply button again. Close

Closes this dialog box without performing any further action. Help

Shows this help text. See also

Farfield Overview, Farfield View, Color Ramp, Farfield Plot, Farfield Source

Farfield Plot Dialog Pages: Plot Mode, Axes, Origin, Array, Decoupling Plane, Phase Center