Phase shift, frequency of 2 analog signals, Diadem 9.0 or 9.1

I have to acquire 2 signals: FORCE (N) and VELOCITY (m/s) for many frequencies parameter in Diadem 9.0 (5 to 150 Hz). This frequency parameter is a analog voltage output signal which is converted in frequency by a frequency vibrator instrument. The measured signals on the vibrator (force and velocity) are considered as SINE Functions. – 1) How do I measure the output frequency of the two signals and how can I save this data ? – 2) How can I estimate the phase shift between FORCE and VELOCITY ? – 3) How can I automate the estimation of the phase shift by the 145 measurement (150-5Hz) ? – 4) Is a continue measurement of Phase Shift depending on the frequency possible ? – Best Regards from Germany and from France.
Jean-Pierre, Junior Engineer Germany

Hello KenT. I have test your DIAdem exemple. Your idea with a stop-time was not bad for measuring the phase shift beetween 2 generators by 1Hz. I have used this formula by many phase shift and it works. I had change the 2 generators frequency by 2Hz, and the formula works not anymore and that is normaly because of the reduce of the periode lenght (this problem have I show on Picture 3 of the PDF Data). On the picture 6 and 7 have I try to make another solution. My new solution works only for frequency from 1Hz to 5Hz. What about frequency like 150Hz ? I don't know if you have understood what I realy want to do, but if you have any idea to resolve my problems, please write to me. '[email protected]'
Jean-Pierre, Junior Engineer Germany
Attachments:
DIAdemTexte.pdf ‏435 KB

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Determine phase shift ben input & output

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Hi Jinio,
Please take a look at the following KnowledgeBase article:
How Can I Determine Phase Mismatch Between Two Channels?

Phase shift base signal

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http://forums.ni.com/ni/board/message?board.id=170&message.id=6956&query.id=101197
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many thanks
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Message Edited by JimmyinCT2 on 01-23-2008 07:17 PM

dahhh, okay, i think i finally figured out what is going on here, and i think im just being somewhat dumb or maybe just assuming to much.
Looking at matts example helped a lot as i see why.
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I think for now, we are going to have to work inside the range [-180,180] and initialize our hardware to 0 phase so we dont start near the inflection point and see if that works.
Message Edited by jimmyinCT on 01-26-2008 07:54 PM

Simulate Signal phase shifting loop

I am trying to use a loop to phase shift a simulated signal across 360 deg. My loop will change amplitude, frequency, offset, but it won't change the phase, does anyone know how I can do this? I have attached a code that shows the fundamental problem.
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Attachments:
SimSigPhaseShift.vi ‏34 KB

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Hello,
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Freq.JPG ‏74 KB
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~~~~~~~~
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~~~~~~~~~
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frequency_determination_example.vi ‏101 KB

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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....
Indrajit
| [email protected] | [email protected] .

Hi Indar,
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National Instruments
Applications Engineer
Attachments:
Hilbertwitharray.vi ‏90 KB

Measure phase shift

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I have got a question relating the measurement of the phase-shift between an in- and outgoing voltage (both analog and the same frequency) of my DAQ-Device.
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[email protected]

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Analog signal duty cycle incorrect

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Attachments:
timing signal 1.JPG ‏44 KB
timing signal 2.JPG ‏47 KB
daqmx gen.JPG ‏55 KB

Hi David,
We found that there seems to be a weird divider between the sampling rate of the analog signal module, the analog signal sample rate, and the f daqmx gen.
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10MHZ
100G s/s
100KHz
100MHZ
10MHZ
100G s/s
10KHZ
1GHZ
1MHZ
100G s/s
10KHZ
10GHZ
10MHZ
100G s/s
1MHZ
100GHZ
10MHZ
100G s/s
10MHZ
100GHZ
10MHZ
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Calculation of phase shift

Hi all,
I am continuously acquiring two sinusoidal signals from the analog inputs of a daq card and saving the samples of the two signals into two different float type arrays. Can anyone tell me that how to calculate the phase shift between these two signals and as well as the peak voltage of the two signals? Please expain me with the help of an example code.
Thanks

Hi AI S
I have gone through the example of phase diff e.g and i have written the following code but when i run it , it gives the max value of 1st sine wave (outarray1) nearly equal (i-e 7.7 volt ) but it should be 8 V pk.
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Here is my code
double outarray1[8192],outarray2[8192] ;
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How do I apply a uniform phase shift to a waveform?

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phase-shift.vi ‏51 KB

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Phase shift, frequency of 2 analog signals, Diadem 9.0 or 9.1

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