H2
PrintThe frequency response function computed as the ratio of the output autospectrum to the "backwards" cross spectrum: Gyy/Gyx.
This technique gives the best performance in the presence of noise for measuring resonances, where the signal to noise ratio tends to be best. For measurement of anti-resonances, the frequency response function H1, gives a better estimate. In a noise free environment, both techniques give the same result.
Since both measurements are based on the same data set, the choice of technique can be made after the data acquisition is completed.
H1, H2, and H3 are all available from Release 6.0 of LabVIEW
Units:
Gain (unitless ratio or dB) and Phase (rad or degrees)
Additional References
Helpful Web Sites:
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