Etude de l`oscilloscope et du GBF

ReCe
ReCe
R1/2
Y
E
R
Re
Y
b)a)
Re
R1/2
Ce
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x(t) T Xeff
X2
eff =1
T∫T
0
x2(t) dt
UM
T0t
f0
s(t) = s0cos 2πf0t
f0
repr´esentation temporelle de s repr´esentation fr´equ
1
f0
s(t)
s0
t
s0
f0
f0
s(t) = a0
2+
∞
∑
n=1
(ancos 2πnf0t+bnsin 2πnf0t) = c0+
∞
∑
n=1
cncos(2πnf0t+ Φn)
anbns
an=2
T0∫T0/2
−T0/2
s(t) cos(2πn f0t)dt bn=2
T0∫T0/2
−T0/2
s(t) sin(2πn f0t)dt

f02f0nf0
nf0anbncn=√a2
n+b2 nn
n→ ∞
•a0
•f0n= 1
•nf0n > 1
s bns an
s(t)
t
cn
f
7f0 f03f05f0
1
f0
Repr´esentation temporelle du signal Repr´esentation fr´equentielle du signal
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Rexp −Rth
Rth 
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