## Electronics

#### Extracting E-Field Values from HFSS

• jmf394
Subscriber

I am considering different designs of broadband coupled microstrip line couplers in HFSS as part of my research. One aspect that is important is the E-Field strength in the gap region oriented from one microstrip line to the other. Using the animate feature with phase, I can find the phase at which the max field across the gap occurs, but there is lack of precision in the colormap that I am looking for.

I tried a number of different operations to try and get this using the fields calculator, but have not gotten anything successfully that makes sense (EG I can get an export that contains X, Y, and Z position and a magnitude, but not having angle information for the vector magnitude gives uncertainty that the magnitude selected is in the correct orientation). Is there a way in HFSS to directly return the max field value in a certain orientation or is there a fields calculator "recipe" that would return this?

• Zeba Naqvi
Ansys Employee

Exporting Vector_E on a certain grid export the x,y,z, followed by the x,y,z components. Have you tried taking dot product of a unit vector in the direction you want the max in, with Vector_E? From that, max value could be obtained, if I am understanding what you are looking for.

• jmf394
Subscriber

This does sound like what I am looking for. However, the export is not making too much sense. I use the following equation in fields calculator:

SclSrf : SurfaceValue(Surface(c), Dot(Vector_E, <0, 1, 0>))

Then I write this to a .fld file. Surface c used above is a rectangle in the YZ plane, but there is more than 1 X position value and there are too many unique Y and Z position values when I look at the .fld file so I do not have confidence in what is being reported by this

• Zeba Naqvi
Ansys Employee

Try only Dot(Vector_E,<0,1,0>) and click export button. In the calculate grid points, zero the x values, and provide your Y and Z values corresponding to the rectangle you created.

• Charlotte Blair
Ansys Employee

Hi jm394,

Be sure you are using complex Mag E Field not Mag E. This will give you all components of the E Field.

Regards,

Charlotte