3.3.1 synchronized averaging. problem propose a time-domain technique to remove random noise given...
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3.3.1 Synchronized averaging
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Problem
• Propose a time-domain technique to remove random noise given the possibility of acquiring multiple realizations of the signal or event of interest
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Solution
• Linear filters fail to perform when the signal and noise spectra overlap.
• Synchronized signal averaging can separate a repetitive signal from noise without distorting the signal
• ECG signals may be filtered by detecting the QRS complexes and using their positions to align the waveforms for synchronized averaging
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Figure 3.12
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Figure 3.13
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Figure 3.14
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For synchronized averaging of order M
The resultant signal has a mean close to x
and a variance equal to
(a standard deviation equal to
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Advantage
No spectral content of the signal is lost !