3 Pulse Oximetry for the Measurement of Oxygen Saturation …
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4.5
5
5.5
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7
x 10
16
Row length
SVR
Fig. 3.9 Typical SVR spectrum obtained from a PPG
to 7 are performed to get the second cycle of the PPG. This process can be continued
endlessly to obtain an artefact and noise-free PPG, cycle after cycle. Figure 3.10
shows a typical example of applying SVD for removing motion artefact from a PPG.
Fig. 3.10 a PPG corrupted with artefact b PPG recovered using SVD method c Dotted line shows
the SpO 2 computed from corrupt red and IR PPG signals, solid line indicates the SpO 2 computed
using recovered PPG signals
75
120
140
160
180
200
220
240
260
280
300
4
4.5
5
5.5
6
6.5
7
x 10
16
Row length
SVR
Fig. 3.9 Typical SVR spectrum obtained from a PPG
to 7 are performed to get the second cycle of the PPG. This process can be continued
endlessly to obtain an artefact and noise-free PPG, cycle after cycle. Figure 3.10
shows a typical example of applying SVD for removing motion artefact from a PPG.
Fig. 3.10 a PPG corrupted with artefact b PPG recovered using SVD method c Dotted line shows
the SpO 2 computed from corrupt red and IR PPG signals, solid line indicates the SpO 2 computed
using recovered PPG signals