Oscillating systems 27
a)
(^00100200300400500)
10
20
30
40
50
60
Frequency (Hz)
|X(f)|
b)
(^00100200300400500)
5
10
15
20
25
30
35
40
Frequency (Hz)
|X(f)| (dB)
Figure 1.21 Chirp signal, linear sweep 100–300 Hz in 2 seconds. a) Spectrum, linear scale. b) Spectrum,
logarithmic scale (arbitrary). c) Autocorrelation function.
c)
-2 -1 0 1 2
-0.4
-0.2
0
0.2
0.4
0.6
tau (s)
R(tau)