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S-parameter dB (S21) of 2D waveguide structure

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Hi, all,

I've built up a In-plane TE waves model with boundary mode analysis to use the solution mode at the excited port. (as attached figure) The procedure I did was pretty much like the waveguide adapter case in the manual (just it's 2D in my case). But when I want to solve the S-parameters, use the the global variables plot and choose the S21 dB parameter. The error pop out and said that "S21dB_rfwe is not a valid expression". I don't know where is not correct to cause this message. How can I get the transmission loss in my structure? Hope that someone can point out if there's anything I did wrong. Thank you so much.

The error details are as below,

Exception:
com.femlab.util.FlException: is not a valid global expression.#S21dB rfwe
Messages:
is not a valid global expression.#S21dB rfwe

Stack trace:
at com.femlab.post.PostPlot.globalEval(Unknown Source)
at com.femlab.post.PostPlot.globalPlot(Unknown Source)
at com.femlab.post.PostPlot.globalPlotMulti(Unknown Source)
at com.femlab.commands.GlobalPlotCommand.evalOnServer(Unknown Source)
at com.femlab.commands.FlCommand.runServerCode(Unknown Source)
at com.femlab.server.ServerProxy.eval(Unknown Source)
at com.femlab.commands.FlCommand.a(Unknown Source)
at com.femlab.commands.FlCommand.eval(Unknown Source)
at com.femlab.commands.a.a(Unknown Source)
at com.femlab.post.PostGlobalPlot.c(Unknown Source)
at com.femlab.gui.dialogs.PostGlobalPlotDlg.applyAction(Unknown Source)
at com.femlab.controls.FlDialog.actionPerformed(Unknown Source)
at com.femlab.controls.FlButton.a(Unknown Source)
at com.femlab.controls.FlButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at com.femlab.gui.e.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)


0 Replies Last Post Mar 23, 2012, 5:36 a.m. EDT
COMSOL Moderator

Hello Yu-Hsin Liu

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