07-13-2016 08:56 AM
Has anyone implemented a transfer function analysis using wavelets?
By analogy awavelet power spectrum can be defined as the wavelet transformation of its autocorrelation function.
Similarly it should be possible to calculate a cross-wavelet transformof two time series and a cross-wavelet coherence.
Can this be doen using LabVIEW?
07-14-2016 10:47 AM
Hi Prof Dee, you can do it with the Advanced Signal Processing Toolkit
Check this intro to the wavelet processing:
https://zone.ni.com/reference/en-XX/help/371419D-01/lvasptconcepts/wa_intro/
07-14-2016 10:53 AM
07-14-2016 01:38 PM
Thanks for your replies. I think I need to supply more details of the problem.
I am looking to find Gain, Phase and Coherence to test the relations between a stimulus and response as is done in the waveform measurements frequency response function.
07-15-2016 11:00 AM
I found a forum where they use Labview with a Matlab script for the coherence analysis, check it out
http://forums.ni.com/t5/LabVIEW/Can-Labview-perform-wavelet-coherence/m-p/1881209#M635706
07-15-2016 11:12 AM
Also chekc the helpme file for the WA Configure Scalogram Indicator VI
Displays the square magnitude or the phase of the wavelet coefficients on an intensity graph.
https://zone.ni.com/reference/en-XX/help/371419D-01/lvwavelettk/wa_plot_scalogram/
07-25-2016 12:49 PM
Thanks for these suggestions. I have reached the conclusion that LabVIEW is not capable of Wavelet Transfer Function Analaysis whereas MatLab is. I don't have Matlab, so will have to wait until National Instruments expands the wavelet function in LabVIEW to match those in Matlab (if ever).