e-spectres
Analyse spectrale
Analyse spectrale
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Analyse spectrale
jean-philippe muller
13- Décomposition des signaux usuels
oscillogramme
spectre
x(t)
E
amplitude
t
4 E ⎡
sin( 3ω
t) sin( 5ω
t)
⎤
x( t) = sin( t ) + + +...
⎣
⎢ ω
π
3
5 ⎦
⎥
T
0 f
3f
5f
f
x(t)
E
amplitude
t
8E
⎡
sin( 3ωt) sin( 5ωt)
⎤
x( t) = sin( t ) − + −...
⎣
⎢ ω
π
2 3
2 5
2
⎦
⎥
T
0 f 3f
5f
f
x(t)
E
t
x( t)
2 E ⎡ 2 cos( 2ωt) 2 cos( 4ωt)
⎤
= + − +...
⎣
⎢1
π
3
15 ⎦
⎥
amplitude
T/2
0 2f 4f
f
x(t)
E
amplitude
t
2E
⎡
sin( 2ωt) sin( 3ωt)
⎤
x( t) = sin( t ) − + +...
⎣
⎢ ω
π
2
3 ⎦
⎥
T
0 f 2f 3f
…
f