How can I measure the phase difference of two input signal?

[AEI_JR]

I am trying to use a PCI 6110E board to measure a TTL speed pulse and vibration signal. Using the speed as a center freq, I want to apply a narrowband filter to the vib signal and then measure the phase difference between the TTL and resulting single tone sine at the zero crossing.

[CraigGraham]

analysis/Waveform Measurements.

"Cross Spectrum (Mag-Phase)
Computes the averaged cross power spectrum of the input signals. Typically,
X signal is the stimulus, and Y signal is the response of the system.
Results are returned as magnitude and phase. Each time waveform corresponds
to a single FFT block and has to be passed individually to this VI.
Averaging parameters specifies how the averaging is performed. This includes
the averaging mode (No averaging, vector averaging, or RMS averaging), the
weighting mode (linear or exponential) and the number of averages. Averages
completed returns the number of averages completed so far. The view cluster
allows you to display magnitude results in decibels, and the phase results
unwrapped or not, in radians or degree
s."

--
Craig Graham
Physicist/Labview Programmer
Lancaster University, UK


"TDICincy" wrote in message
news:506500000008000000DC390000-1011517314000@exchange.ni.com...
> I am trying to use a PCI 6110E board to measure a TTL speed pulse and
> vibration signal. Using the speed as a center freq, I want to apply a
> narrowband filter to the vib signal and then measure the phase
> difference between the TTL and resulting single tone sine at the zero
> crossing.

[Ben]

Hi TDICincy,

I agree with Craig's suggestions and would like to make an additional comment. Filtering will generally introduce a phase shift in a signal.
So,
Pass both signals through the same filter,
or
Use a zero-phase shift filter.

Ben