Search found 9 matches

by chrisf
Tue 25 Feb 2014, 14:30
Forum: Usage
Topic: Inverted F example meshing
Replies: 9
Views: 12609

Re: Inverted F example meshing

Thinking about it some more, I guess that the extra ground plane reflecting energy back into the antenna (and other ground plane) is bound to increase the simulation time as it takes longer for the energy to escape?
by chrisf
Tue 25 Feb 2014, 14:17
Forum: Usage
Topic: Inverted F example meshing
Replies: 9
Views: 12609

Re: Inverted F example meshing

I have only seen this extreme jumps when I accidentally had my active structure too close to the PML-BC. A slow decay (or staying at -20 for a long time) is typical for a resonance and completely normal... Having done some more tests it seems that, as you suggest, this is a natural consequence of t...
by chrisf
Tue 25 Feb 2014, 07:59
Forum: Usage
Topic: Inverted F example meshing
Replies: 9
Views: 12609

Re: Inverted F example meshing

I've been adding further ground boxes to the inverted f example to get an understanding of the effect of metal work in the vicinity of this antenna. I think these are working OK but, often, I'm finding that as the simulation runs, the reported 'energy' gets below -20dB in a few minutes but then, rat...
by chrisf
Mon 24 Feb 2014, 15:29
Forum: Usage
Topic: Inverted F example meshing
Replies: 9
Views: 12609

Re: Inverted F example meshing

That's reasonably (from my limited understanding!) clear. Thanks again. I adjusted my polygon IFA definition to cut out the port and that now produces a sensible mesh and simulates in a reasonable time (2min vs an hour). I still get some warnings - do I need to worry about these? warning: lines: 9@3...
by chrisf
Mon 24 Feb 2014, 15:04
Forum: Usage
Topic: Inverted F example meshing
Replies: 9
Views: 12609

Re: Inverted F example meshing

Thanks very much!

If I understand the fix correctly, you've removed the overlap between the IFA conductor and the port?
I ask because I first saw the problem when using a polygon for the IFA definition.
Is the correct approach to not overlap the port with the conductor but have them adjacent?
by chrisf
Mon 24 Feb 2014, 05:19
Forum: Usage
Topic: Inverted F example meshing
Replies: 9
Views: 12609

Inverted F example meshing

I'm having problems when I alter the inverted f example code and clearly don't understand how the meshing is supposed to work. If I change the height of the short circuit stub from 8mm to 7.9mm (or 8.1mm), I get a run of 'warning: division by zero' and a very dense mesh along the edge of the ground ...
by chrisf
Sun 23 Feb 2014, 06:20
Forum: News
Topic: Release Notes on openEMS v0.0.31
Replies: 8
Views: 48907

Re: Release Notes on openEMS v0.0.31

[*] new tutorials and examples: a bent patch antenna , dipole-SAR , MRI loop coil , MRI birdcage , patch antenna phased array and an inverted F-antenna example I can't see the inverted F-antenna example anywhere. I'd be really interested to learn how to do that. Did I miss it? EDIT: Sorry, I found ...
by chrisf
Fri 21 Feb 2014, 20:25
Forum: Install
Topic: Binaries for Linux
Replies: 10
Views: 26445

Re: Binaries for Linux

Thanks, Thorsten.
All good with the build on the master branch.
by chrisf
Fri 21 Feb 2014, 13:38
Forum: Install
Topic: Binaries for Linux
Replies: 10
Views: 26445

Re: Binaries for Linux

I only removed libc.so* and ld-linux-x86-64.so.2 and put it all into an archive: http://www.openems.de/download/linux/openEMS_v0.0.31_x64.tar.bz2 Maybe you give it a try. It worked on my Ubuntu 13.10, but that is newer than 12.04 and not older like your Debian. But if it does not work you "simply" ...