Телекоммуникационные системы
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3.18 –
3.4
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3.4.1
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3.4.2
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3.4 f, |
3.19 –
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3.19 «
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3.4.3 ( ITU-T)
ITU-T -
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L =2500 , -60 ( -
3.20).
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3.20 – 2500
( ), -
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2500 : P 10000 0 ( ) .
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P 2500 0 , P 7500 0 ,
P P P ( ) .
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P 1 7500 0 2500 3 0 , 1 3 0 .
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: -
P : P : P 1:1: 2.
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P : P 1:1.
57
3.4.4
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3.21 –
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k T f , |
(3.1) |
k 1.38 10 23 / – ,
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10lg( ) 10lg( N) n , |
(3.3) |
n 10 lg(N) – .
1 . ,
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(3.4) |
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(3.5) |
58
– ;
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(3.4),
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= 1 + 2.
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(0) = Pcni(0) = . |
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(3.7)
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1 . (3.7)
p , .
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+ 10 lg |
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( 3.22).
( -
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- – d – 10 lg |
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3.22 – l0
3.4.5
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( 3.23). ,
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3.23 – :) ;)
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60
( ) . -
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3)-
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II |
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P I |
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II p II – II ; |
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II – II; |
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II p – II |
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p II - |
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P II |
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II=p I – A0. |
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l I 0 . |
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A 30 |
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(3.11) |
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A30 0 l . |
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I = II , |
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3l = A0 |
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, .
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