Search found 1528 matches

by thorsten
Wed 31 Aug 2022, 20:26
Forum: Development
Topic: CUDA GPU Acceleration
Replies: 5
Views: 694

Re: CUDA GPU Acceleration

However, I'm not sure if Accelware (their GPU reference) has a fantastic GPU implementation compared to market leaders like CST It is my understanding that there implementation is used by one of the bigger vendors and is comparable in speed to that of CST. But I do not really know. Overall, 6x spee...
by thorsten
Mon 29 Aug 2022, 20:18
Forum: Development
Topic: CUDA GPU Acceleration
Replies: 5
Views: 694

Re: CUDA GPU Acceleration

But to make it clear, if you are able to speedup openEMS using CUDA, I'm sure many people would be very happy to give it a try...
That said, keep at it. Would be very cool to see...
by thorsten
Mon 29 Aug 2022, 20:14
Forum: Development
Topic: CUDA GPU Acceleration
Replies: 5
Views: 694

Re: CUDA GPU Acceleration

The numbers you need to compare are not the RAM speeds but the L1-L3 Cache (and size) of a CPU. A GPU simply does not have the same amount of central cache as a CPU. The fastest FDTD to my knowledge on a GPU (Tesla P100) is <4.5GC/s (see here ) But that pales in comparison to the 10+GC/s possible on...
by thorsten
Mon 29 Aug 2022, 19:55
Forum: Usage
Topic: Is openEMS capable of computing the phase center for farfields?
Replies: 5
Views: 572

Re: Is openEMS capable of computing the phase center for farfields?

Maybe you can do some research for papers how to do this the best way? If it is not too wild you could try to implement it. ;)
by thorsten
Mon 29 Aug 2022, 19:53
Forum: Usage
Topic: Error loading an xCat Phantom using Ubuntu 18.04
Replies: 1
Views: 243

Re: Error loading an xCat Phantom using Ubuntu 18.04

I assume the error is produced from openEMS itself trying to run the model? Or is this error from the Matlab/Octave interface? Does the Windows Version of openEMS run fine or just looking at the file? Maybe openEMS expects a different data type? I have not worked on/with this part for a very long ti...
by thorsten
Mon 29 Aug 2022, 19:47
Forum: Usage
Topic: Incorrect S-parameters (|S21| < -45dB) for simple rectangular waveguide?
Replies: 2
Views: 361

Re: Incorrect S-parameters (|S21| < -45dB) for simple rectangular waveguide?

Maybe this is indeed something simple. A PML_8 is 8 cells thick. If you have indeed placed your ports only 5 cells from one end, then they would sit inside the PML? That would explain why S11 and S21 are low, because you only very efficiently are pumping energy into the PML... Maybe check for this a...
by thorsten
Tue 16 Aug 2022, 19:23
Forum: Usage
Topic: Excitation signal - different from CST?
Replies: 6
Views: 1066

Re: Excitation signal - different from CST?

I'm not really sure what you mean. It is no problem in openEMS to define f_0 as 0 and use an unmodulated Gaussian Pulse just like in CST and I think many openEMS Tutorials do it just like this. But as I said, in some cases you want a DC free signal, e.g. for waveguides where you should not excite th...
by thorsten
Mon 15 Aug 2022, 18:08
Forum: Usage
Topic: Excitation signal - different from CST?
Replies: 6
Views: 1066

Re: Excitation signal - different from CST?

I think the definition in CST is just plain wrong. A pulse from 0 to 2 GHz has its center at 1 GHz and is thus "DC free" (mostly). Which is *not* what CST is obviously using. What they use in fact is a pulse centered around 0 with a bandwidth ot 4GHz (or 2GHz cufoff). If you configure openEMS to use...
by thorsten
Tue 19 Jul 2022, 12:25
Forum: Usage
Topic: Ex,y,z component far-fields from CalcNF2FF
Replies: 10
Views: 2739

Re: Ex,y,z component far-fields from CalcNF2FF

I'm not I understand everything you were asking, but the parts that I think I understand I do not agree with ;) The near-fields are all recorded in frequency domain, because (afaik) nf2ff does not make any sense in time-domain? In short, far field patterns are calculated for the given frequencies an...
by thorsten
Fri 08 Jul 2022, 21:50
Forum: Usage
Topic: Ex,y,z component far-fields from CalcNF2FF
Replies: 10
Views: 2739

Re: Ex,y,z component far-fields from CalcNF2FF

Hi,

I'm a but confused about your request. lambda/20 is a length (e.g. in meter) and thus has little to do with time-domain??

Furthermore the nf2ff (at least the one in openEMS) cannot handle time-domain input and/or output...

regards
Thorsten