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Signal Conditioning

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Labview algorithm for voltage threshold pulse counting

I have NI PCI 6024E daq card and im using labview  2010 with daqmx.

I have a signal which contains pulses that i have to count. The problem is that in addition  to the pulses there are some small voltage spikes as well in the signal. When i try to count the rising  edges using counter, it counts the small voltage unwanted spikes as well and therefore gives a false reading. 

 

I tried to find a way so that a threshold could be set for the counter so that counter counts only the pulses that cross that threshold but i came to know that counters doesnt have such threshold  feature. 

 

I need suggestions about how can i approach this issue? 

Preferably  i would like to implement  a software solution to this problem. 

Thanks alot

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Not a software fix: How about a simple RC filter ?    

(dedicated counters sometimes have a analog threshold setting... , but that doesn't help here unless you build a comparator with settable  threshold)

 

and isn't there a debounce filter for the counters, that maybe work?  Depending on the actual pulse and spike timings  you didn't 'valued' 😉

 

 

A software solution would be the median filter as a preprocessing for the analog  pulse counter, that will remove spikes and 'sharpen' the edges.

 

Greetings from Germany
Henrik

LV since v3.1

“ground” is a convenient fantasy

'˙˙˙˙uıɐƃɐ lɐıp puɐ °06 ǝuoɥd ɹnoʎ uɹnʇ ǝsɐǝld 'ʎɹɐuıƃɐɯı sı pǝlɐıp ǝʌɐɥ noʎ ɹǝqɯnu ǝɥʇ'


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