Phase Shifting of Sine Wave acquired using DAQmx board

[Raza]

Hi,

We are trying to implement a phase shifter in my Labview program. We are acquiring sine wave from an analogue function generator in our labview program and trying to find a way of controlling the phase of that sine wave in my labview program.

Regards,

Raza.

[Laura F.]

Hello Raza,

I am a little confused about what you are trying to do.  It seems you are acquiring a sine wave signal using a DAQ board.  You would like to take this sine wave and change the phase of it?  Why are you trying to do this?  Are you saving the data to file or displaying it on a graph?  You could just change the index or time that the array is plotted against, changing the phase. 

Please let us know a little more about what you are trying to do.

Thanks,

Laura

[Raza]

Hi Laura,

I am not simply trying to plot data, my idea is to control the phase of the incoming sine wave from the DAQ board to Labview. So, I am interested in implementing a dial control on my Labview VI to change the phase of the incoming sine wave.

Regards,

Raza.

[rpursley8]

Try this vi.  It uses a Hilbert transform and some trig identities to generate the signal.  This is only a simulated version, so you will have to see how it works with an input.

[rpursley8]

Here is the diagram, if you don't have LV 7.0

[wgm2193]

This only works if you know the frequency of the input sinusoid. How do you implement a phase shift when you don't know the input frequency or the frequency changes with time?

[rpursley8]

It is independent of the input frequency, but shifting the frequency will make the Hilbert Transform block have to settle out to the new frequency.