imaginary part of feed.R

How to use openEMS. Discussion on examples, tutorials etc

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Joined: Tue 25 Aug 2020, 12:01

imaginary part of feed.R

Post by totaka » Tue 25 Aug 2020, 12:13


I just started using openEMS and wondering if I can set the feed impedance with imaginary part as well
for addLumpPort. I tried something like feed.R = complex(150, -70), but the simulator gives warning, although
simulation itself will run.

"Error in LumpedElement-Property Resistance-ValueSyntax error; Operator expected"

Does this mean that feed.R should have no reactance? Thank you in advance.

Kind regards,
Toshinori Otaka

Posts: 1425
Joined: Mon 27 Jun 2011, 12:26

Re: imaginary part of feed.R

Post by thorsten » Tue 01 Sep 2020, 21:45


the FDTD method is a time domain method (TD). Thus it does not have any concept of complex numbers or values.
Only after you convert data from time domain into frequency domain (via FFT or DFT) during post-processing you have complex values.
Thus you cannot use complex values for anything or anywhere for the FDTD engine/setup.

best regards,

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