CST MWS端口是否必须紧贴模型表面设置么？

RT，在端口设置的时候会有两个距离选项，当仿真出现3 grindlines(http://bbs.rfeda.cn/read-htm-tid-81152.html)的错误时，我改变了Zpos，就可以进行仿真了，但我不知道这样做与紧贴模型表面设置有什么区别，麻烦各位指教一下。

参照端口的帮助文件吧，这两个距离的意义是不一样的

我的cst帮助文档不能用，麻烦能发一个么

帮助文件200M。没办法。

帮助文件《Waveguide Port》
Free normal position: Please activate this button to define an internal port, i.e. a port location inside the calculation domain. This check button is only enabled for a Free or Full plane transversal range setting (see above).
The value for the normal position can be inserted in the corresponding  X/Y/Zpos text field.
Note: Deactivating this button will always locate the port on the lower or upper boundary of the calculation domain, corresponding to the definition of the lower or upper port orientation.
Distance to ref. plane: Specifies the distance to your reference plane to obtain the correct phase information for the S-parameters (deembeding). Positive values move the reference plane outwards, negative inwards. The deembeding can also be performed after the calculation run. See Results S-Parameter Calculations Deembed S-Parameter.... The picture below shows a waveguide port with negative distance to the reference plane, i.e. the reference plane is moved inwards.

好的，谢了！我再仔细看看