Biomedical Engineering Reference
In-Depth Information
1.5
1
0.5
0
0
0.5
1
1.5
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5
−
0.5
−
1
−
1.5
TIME (s)
(a)
1
0.8
0.6
0.4
0.2
0
0
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1
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−
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TIME (s)
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(b)
FIGURE 11.3
(a) Periodic sine wave signal
x
(
t
) ¼ sin(o
t
) with period of 1 Hz. (b) Transient signal
y
(
t
) ¼
e
0.75
t
sin
(
o
t
) for the same 1 Hz sine wave.
used for the diagnosis of neuromuscular disorders, is a random signal. Stationary random
signals have statistical properties, such as a mean and variance, that remain constant over
time. Conversely, nonstationary random signals have statistical properties that vary with time.
In many instances, the identification of stationary segments of random signals is important
for proper signal processing, pattern analysis, and clinical diagnosis.
