Телекоммуникационные системы
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91
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. 4.42 –
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( 4.43).
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4.43 –
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( 4.44).
g(t) -
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92
g(t)
4.44 –
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K0
K( ) 0
y(t)= Ê0 B
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4.45 –
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2 1 ,
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0.213.
g(t), -
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K 0 |
( 0,54 ) 0,46 cos |
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g(t) 0.006.
3. .
93
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, 4.46.
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4.46 –
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sin B t |
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( 4.47), = , .
B
4.47–
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1);
2)t=n g(t) .
.
94
, g(t–k ) ( 4.48, ).
( 4.48, )
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4.48 –
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– ,
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4.5.2 ( -30)
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, 125 .
N ( -
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-30/32 ( ITU-T G.703) 30 2
, ISDN BRI N=3, 64
16 .
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64 .
( )
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N
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-30 = 125 0.24 .
2 8 32
-30 .
( ) -30 -
4.5.8. 32
), ( 1 15; 17 31)
( 0 16).
n (n=1–8).
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1 4 5 8, 1 2 56, .
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4.4.
4.4 -
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14 15 16 17 30 31 |
96
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4.49 – -30
97
=16 =16 125 =2 ,
50
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6
». . ,
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– .
0 2 8 -
8 . 1
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>10–3, >10–5) .
-30 -
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4.6
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( . 3): ,
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98
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4.50 , .
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(011) |
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(010) |
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(010) |
1.5 |
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3 4 5 |
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4.50 –
4.50, (
– 000) . -
0.
4.50, 001 -
, 0 – 0,5 .
1.5 , 2.5 .
/2.
4.6.1
-
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+ i . |
(4.5) |
i .
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4.51 .
99
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(n+1) |
(n+2) |
4.51 –
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1);
2)( -, .). , -
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r n, n, n <<
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S2 – S .
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= 2 + b2. |
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(4.6.3) (4.6.4), -
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2 2 S2 a2 b2 , |
(4.10) |
S |
2 .
(4.6.5) -
100 |
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10lg[ 2 ( 2 + b2)]–1 . |
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a b, , -
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n 810 = 34 .
4.6.2
( 4.50).
-
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. 4.52 -
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, 4.50, .
. 4.52 –
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4.3 4.4.