phase difference calculation myrio

[santamaria]

Hi,

I am trying to find phase difference of the sine wave of 1kHz acquired from microphones. I am successfully able to calculate the phase difference from the sine waves acquired through function generator but when i connect myRIO to mics, the data is successfully acquried and displayed on the graphs but the phase difference keeps varying. I have attached my vi also. Pls help.

[Call.Me.Wilbur]

It’s very possible that the behavior you’re seeing is expected. The signals recorded by the microphones will be slightly different due to varied distance from the source of the sound. Even if you had the microphones very close together they still may pick up slightly different signals depending on their angle.

How big is the phase difference that you’re seeing? Does that difference change when you move the mics closer together or further apart?

[santamaria]

I havent checked the phase by changing the distance between the microphones.

Is there a way to keep the display constant, the value keeps changing by +-5 degrees ? Or can u guide me how can i take the average of values. I tried the build array function and then used the mean block. But it doesnt seem to work.

[Call.Me.Wilbur]

If you want to take a running average you could use the Mean Point by Point VI. Take a look at the documentation for it here. You can just input the phase difference and a sample length for however many points you want to maintain an average.