interferencia intersimbólica
TRANSCRIPT
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= 1
2P () +
1
2P () = 2
1
2
1
=
1
p (t) = {1 ; t = 0
0 ; t = ± b
= 12tb
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P (f ) = f
f b
+ H 1 (f ) p (t) = 1
tb
ttb
+ h1 (t)
h1 (t) =∞ −∞
H 1 (f ) e jωt
= 2∞ 0
H 1 (f ) (ωt)
h1 (t) = 2 −β
H 1 (f ) (ωt) + 2+β H 1 (f ) (ωt)
c d v : { : f = −x
: f = +x
:
h1 (t) = 2β 0
H 1
2 − x
2π
2 − x
+ 2β 0
H 1
2 + x
2π
2 + x
: H 1
2 + x
= −H 1
2 − x
h1 (t) = 2β 0
H 1
2 + x
2πt
2 + x− 2πt 2 − x
h1 (t) = −4β 0
H 1
2 + x
[ (πf bt) (2π )]
h1 (t) = −4 (πf bt)β 0
H 1
2 + x
(2π )
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G (f ) = |P (f )|2
;
P (f ) →
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Ak | P R (f ) |=| P (f ) | | H T (f ) | | H c (f ) | | H R (f ) |→ (1)
:
S T =∞ −∞
|P (f )|2|H T (f )|2
(1) :
S T = Ak2∞ −∞
|P R(f )|2
|H c(f )| |H R(f )|
σ2
Ak2 = S T
∞R
−∞
|P R(f )|2
|Hc(f )| |HR(f )|
y
σ2 =∞ −∞
(f ) | H R (f ) |2
:
Ak2
σ2 = S T ∞R
−∞
(f )|H R(f )|2
∞R
−∞
|P R(f )|2
|Hc(f )| |HR(f )|
→
|∞ −∞V (f )
W (f ) |≤
∞ −∞| V (f ) |
2
∞ −∞|W (f ) |
2
V (f ) = k W (f ) :
W (f ) = |P R(f )||H C(f )||H R(f )|yV (f ) =| H R (f ) |
(f )
:
| H R (f ) | (f ) = k
|P R(f )|
|H C(f )||H R(f )|| H R (f ) |2 = k
|P R(f )|
|H C(f )|√
(f )
| H T (f ) |2 = Ak2 | P R (f ) |
(f )
k | H C (f ) | | P R (f ) |2
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