Search found 156 matches

by Hale_812
Mon 10 Feb 2020, 07:55
Forum: Usage
Topic: What is the relation of amplitude returned by harminv() to abs(fft(voltage)) ?
Replies: 0
Views: 52

What is the relation of amplitude returned by harminv() to abs(fft(voltage)) ?

It appears, harminv is binary compiled, which makes sense when talking about performance.
But I could not get a relation of harminv amplitudes to corresponding components of FFT from voltage.
How can I bring one o another in order to pinpoint the resonant peaks on the spectrum?
by Hale_812
Mon 10 Feb 2020, 05:04
Forum: Feedback
Topic: bug in InitFDTD 'MaxTime'
Replies: 5
Views: 130

Re: bug in InitFDTD 'MaxTime'

1000000000 it is crazy large. looks like a precision problem when timesteps are very small. timestep is 4.28692e-013 stoptime is 1e-7 there should be only 233267 timesteps, but I already got 789965 steps today. is something wrong here? stoptime=1e-7; FDTD = InitFDTD('CoordSystem', 0, 'MaxTime', stop...
by Hale_812
Mon 10 Feb 2020, 01:43
Forum: Development
Topic: Time data in vtk dumps
Replies: 2
Views: 87

Re: Time data in vtk dumps

I mean, I can extract, but it is very hard feeding the time data to paraview. If it is inside, it is accepted automatically for every "frame" as exact time.
by Hale_812
Fri 07 Feb 2020, 08:39
Forum: Feedback
Topic: bug in InitFDTD 'MaxTime'
Replies: 5
Views: 130

Re: bug in InitFDTD 'MaxTime'

No, Thorsten, it does not work. Not always. And I don't know why. I set the stoptime at 1e-7 and see how it runs beyond 1.5e-7. Sometimes it stops, sometimes not. WHy do I do this? I excite a resonator with feeding strips and lumped port, a port load is at the other side. It is inside MUR box. T\Whe...
by Hale_812
Thu 06 Feb 2020, 04:14
Forum: Usage
Topic: Unexpected result after irradiating a PEC plate
Replies: 3
Views: 129

Re: Unexpected result after irradiating a PEC plate

I've been making scattering simulations, with a help from Thorsten, including irradiation of weird surfaces. It was a time ago, so I don't remember details, but it works like this: when is the the wave called "plane"? only when d/x=d/dy=0, where propagation is along z. Is it possible if we place a s...
by Hale_812
Thu 06 Feb 2020, 01:47
Forum: Development
Topic: Time data in vtk dumps
Replies: 2
Views: 87

Time data in vtk dumps

Dear Thorsten,
Can you implement TimeValue (at least optional) field in vtr dumps for ParaView showing the propagation time? Maybe setting time-scale like "0"(integer steps),"1e-6", "1e-9" would be useful?
by Hale_812
Wed 05 Feb 2020, 06:42
Forum: Usage
Topic: The problem with leaky resonator characteristic modes? How?
Replies: 0
Views: 47

The problem with leaky resonator characteristic modes? How?

It is known that FDTD is hard to analyze closed cavities where the signal does not decay well. But there is an opposite problem. Lets consider a resonator with PEC on the top and bottom, but PMC on the sides! When loaded with 2 perfectly matched ports, it works more or less as a filter (if there is ...
by Hale_812
Mon 03 Feb 2020, 02:23
Forum: Usage
Topic: Excitation of a resonator in polar coordinates.
Replies: 2
Views: 93

Re: Excitation of a resonator in polar coordinates.

the field. The sourceit is broken into two dipoles. it leaks in the center, giving preference to wrong modes. I was wondering, if there is a right way of exciting the field uniformly along the diameter line? But looks like no. at the moment I am changing the mesh generator script to rectangular coor...
by Hale_812
Mon 03 Feb 2020, 02:19
Forum: Feedback
Topic: bug in InitFDTD 'MaxTime'
Replies: 5
Views: 130

Re: bug in InitFDTD 'MaxTime'

:)

really, that should be long. can I ask for additional stop condition in future version if you plan do publish such? Since the real time monitor is already implemented it looks like a natural feature.
by Hale_812
Fri 31 Jan 2020, 04:01
Forum: Feedback
Topic: bug in InitFDTD 'MaxTime'
Replies: 5
Views: 130

bug in InitFDTD 'MaxTime'

I use FDTD = InitFDTD('CoordSystem', 1,'MultiGrid',conf.r/2, 'MaxTime', (60*60*10)); for calculating during 10 hours, each made up of 60 minutes, each made up of 60 seconds. However, the simulation does not stop after 15+ hours. In the help it is written that 'MaxTime' is a "real" time of simulation...