Hi, ***I thought I should note that I am working with tech support on this, but was also hoping that someone on the board might have some experience with this.*** I have a sinusoidal voltage signal in which the frequency varies over time. I am measuring the output of an engine, and in a given run the engine starts, runs for a few seconds (producing the sinusoidal voltage), and then stops. I want to plot the frequency of the signal as a function of time through the run. To do so, I'm using the joint time-frequency analysis tool. The tool can also perform order analysis also, but what I'm using it to do is basically break my data up into time intervals, apply the FFT on each, and then combine the results in a 3d plot. The plot looks pretty much as I expect it should, with a curve that starts at the onset of the engine, then has a slowly varying frequency, and then stops at some point. My concern is that from my data I can see exactly when the engine stops - however the 3d result plot seems to imply that the engine is still running long after the data says otherwise - the curve continues quite a bit farther than it should. The amount by which it extends after shut off is more than one interval (it's actually quite a few intervals) so it's not a result of averaging over a given time interval. I particularly want to try to compare the 3d result with another data set to try to show a dependence (or a lack thereof), and it is quite a problem to have the engine seeming to be running when the other variable shows that it could not be. Has anyone used this tool in diadem before? I found that there are many more methods for joint time-frequency analysis available in Labview (I downloaded the Labview joint time-frequency analysis toolkit) but I'm not sure how to write a program to use it. From the manual, apparently which method you should use depends on the type of data set you want to analyze - there's the short time Fourier transform, Gabor spectrograph, Wigner-Ville distribution, etc., and I can't find any information about which one the diadem toolkit is using. Any suggestions would be greatly appreciated, Myra

DIAdem

joint time-frequency analysis tool help

Hi Brad,

the discussion ends here in 11-042016 with no message about finishing your planned improvements. Is there any progress for the actual Diadem 64 bit versions?

Best regards,

Petr

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DIAdem

joint time-frequency analysis tool help

Re: joint time-frequency analysis tool help