Extracting orders, Figure 3-4. gabor coefficients, Extracting orders -6 – National Instruments Order Analysis Toolset User Manual
Page 36
Chapter 3
Gabor Transform-Based Order Tracking
LabVIEW Order Analysis Toolset User Manual
3-6
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VI to perform the mask operation. Refer to the LabVIEW Order Analysis
Toolset Help for information about the Template to Mask VI.
You can consider the mask operation a time-variant bandpass filter in the
joint time-frequency domain. The center frequency of the passband equals
the frequency of the order curve. The number of elements set to TRUE
determines the bandwidth of the passband.
Extracting Orders
Figure 3-4 illustrates the order extraction and signal reconstruction
process.
Figure 3-4. Gabor Coefficients
Figure 3-4(a) shows a frequency-time spectral map after the Gabor
transform.
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Time (s)
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(a) Original Signal
(b) Mask
(c) Masked Coefficients
(d) Gabor Coefficients of the
Reconstructed Signal
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