7
:
.
: .
: , .
.
, , - -, -; , ( ), (6,5 SECAM 5,5 PAL) , , ; ; , , () .
- , .
3.
- , .
. e(t), {n} = n(k) (n = , 1, 2, 3,... ; 
; m , . . , () {Un(t)} U(t). , .. m=2. , .
: QPSK , QAM COFDM (Coded Orthogonal Frequency Division Multiplexing) .
(; -, ; amplitude shift keying ASK). 1 - (5.9, ) τ ( ), 0 () .
(; -, ; frequency shift keying FSK). - (5.9, ) f0 1, f1 0.
(; -, ; phase shift keying PSK). - (5.9, ) 180 1 0 0 1. - () , .
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(; ) (; differential phase shift keying DPSK), - (5.9, ). , 2, 4 8. , . , , . 1. , 1800 1 - λ , 1 , 180. , () . , .
,
, (-4;
; . Quadrature phase shift keying QPSK). -4 (QPSK) , . , () .
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5.9 - : ; ; -;
-; -;
: (00, 01,10 11) , 90, 180, 270 45, 135, 225, 315 . , (8 ), . .
1. .
2. MOD ► Type ►ASK .
- , .
3. 200.
. Freq. , , . . . MOD.
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