If I have a wave that contains multiple frequencies , how can I highlight where in the data a specific range of frequencies occur? For example, if the data has frequencies between 1 and 500Hz but I am interested in finding where frequencies from 3-5 Hz are present, how would one go about doing this? The duration of the wave is about a minute long.
Thanks for your suggestion.
I was able to get a magnitude vs frequency graph using this command but this is not quite what I want.I am new to signal processing so I am not quite sure if this is something trivial that can be achieved easily. Is it possible to highlight in the original wave when certain frequencies are most dominant?
If your data is a narrowband signal, you can calculate the instantaneous frequency (frequency vs time) (see also the example in displayhelptopic "HilbertTransform")
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J. J. Weimer
Chemistry / Chemical & Materials Engineering, UAHuntsville
May 9, 2013 at 09:53 am - Permalink
I was able to get a magnitude vs frequency graph using this command but this is not quite what I want.I am new to signal processing so I am not quite sure if this is something trivial that can be achieved easily. Is it possible to highlight in the original wave when certain frequencies are most dominant?
May 9, 2013 at 02:20 pm - Permalink
hilberttransform/dest=dataH data
instantphase=atan2(data,dataH)
unwrap 2*pi, instantphase
differentiate/meth=1 instantphase /d=instantfreq
instantfreq/=2*pi
For broadband signals, one can calculate a sonogram / spectrogram (see
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- Fabrizio</span>
May 9, 2013 at 03:41 pm - Permalink
John Weeks
WaveMetrics, Inc.
support@wavemetrics.com
May 10, 2013 at 09:36 am - Permalink