how to count the tones number in the waveform ?

[walterdell]

see the attached vi,i want to know the tone numbers in the waveform. how to programm the labview code? thanks a lot for your help and modified vi attached.

[ShotSimon]

walterdell,

I noticed your post remains unanswered.  If you are trying to detect exact frequencies I would recommend looking into DTFM detector algorithms many of which are posted within this forums.  These are designed with specific tones in mind but the same idea applies to any tone.  If you are just trying to count the groups and you are guaranteed a certain duration between them, could you implement a simple amplitude trigger with delay algorithm?  You will have to handle the different amplitudes possibly by detecting and removing the DC offset.  I handled it by taking an average and subtracting this scalar across the whole array (see attached).  Also you need to adjust the trigger delay.

You will get 9 and 10 for the number of tones for the waveforms shown.  Is this what you are looking for?  Sorry for the late post. 

Regards,

SS  

Message Edited by ShotSimon on 01-03-2008 04:26 PM

Message Edited by ShotSimon on 01-03-2008 04:27 PM

[ShotSimon]

Make sue to set the Trigger Amplitude to 0.02, for some reason the make current values default is not taking when I post.  SS