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phase shift a signal data

hi all

          i want to phase shift a signal of 90 degree. i am having the signal data  as 1d array,using the data i want to shift the phase of the the signal .....any one....

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Indrajit

| indrajitbarve@gmail.com | indar_indar2005@yahoo.co.in .
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There is an option called "Rotate aray".Do u mean that?
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Do you want to time shift or phase shift?  The Hilbert Transform  in the Signal Processing>>Transforms palette is used to phase shift signals 90 degrees.
Randall Pursley
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Hi Indar,

 

You have several options--however the best is to devise a formula for the phase shift and then put this is the formula node in LabView to process the array data. Alternatively, you can use the Hilbert Transformation to apply a uniform phase shift to waveform data. Please refer to Echo Detector.vi or my simple example attached below.

 

Ipshita C.

National Instruments
Applications Engineer
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And how i can do phase shift with 120 degree?

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What is the nature of the signal?  For a sinusoid, a phase shift shifts the entire waveform in time by an amount -(phase shift in radians/(2 pi f), so a 1Hz sinusoid shifted 90° = pi/2 would be shifted in time -(pi/2)/(2 pi) = -0.25 seconds.  The usual convention is a phase lead (positive numbers) means the waveform is advanced, so the "delay" is negative.

 

If your signal has a variety of frequencies in it, did you want to phase shift all of them by the same phase?  Note that since the phase shift will shift-in-time depending on the frequency, the components of your composite signal will be shifted differing amounts, potentially changing the nature of the signal.

 

Bob Schor 

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  How can I make Signal ( one dimensional array of ) in to phase shift of 90 degree?

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Sigh.  You really need to take a Signal Theory class, then you'll understand your question is meaningless, particularly without knowing the nature of the signal (which is what I asked earlier).  So here's a method guaranteed to work for any signal:

  • Plot the signal on a piece of paper.
  • Rotate the paper a quarter turn to the left.
  • Voilà, a phase shift of 90º.

Bob Schor

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Bob 😄

Task solved ... see my sig 😉

 

And they never tell us why they need to do it. Signal theory classes help, however in my experience you need to deal/play with real tasks for some time to get a understanding*.  For the class/test it's more often a simple (but still complex) application of math rules.

 

*)

How comes that I have areal and  imaginary  signal part in my real copper wire...

Why (and why not!)  my signal representation is equivalent  in time and/or frequency domain...

Effects of discrete time ...

 

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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