, 1.4, . 8.
b (t) = A 1sin(2p f 1 t) + A 2sin(2p f 2 t) + A 3sin(2p f 3 t) ( ). A 1, f 1, A 2, f 2, A 3, f 3, f 0, m .
: , , . : . b (t) . .
1.4, . 9.
. f 0 = 2500 . S : b (t) = sin 2p ft, f , b (t) = 0,5 sin 2p70 t + 0,5 sin 2p200 t.
: , D f Dj . : .
7.1 .
7.2 .
7.3 .
7.4 . 5.2...5.4, 5.65.9 ( , ).
7.5 . 5.2...5.4, 5.65.9 ( , , ..).
7.6 , , 100- .
1.5
1.1 - , - -2.
1.2 - - = 2 4 -2.
2.1 b (t) () 1 0, . 1, 0. R (/).
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2.2 s (t) , :
, (1)
si (t), i = 0, , 1 ();
( );
i - , k - .
, . : - , - , - , ‑ , - .
= 2, s (t), s 0(t) 0, s 1(t) 1. > 2, () s (t). , = 4, 8, , 2 n, n . si (t) n = log2 M b (t). , . = , : = log2 M.
2.3 - -2 :
, (2)
ai , n , si (t);
A (t) , ;
f 0 .
(2) , , si (t) , f 0. si (t) A (t).
A (t) , , . si (t) , , A (t) . (. 1), - -2:
, (3)
f = 0,5/ ;
a (0 £ a £ 1).
(3) (2).
2.4 . - ‑2 (. 2). , , .
-2: 0 a 0 = 0, 1 a 1 = .
-2:0 a 0 = ; 1 a 1 = .
-4:00 a 0 = ; 01 a 1 = 3 ; 10 a 2 = ; 11 a 3 = 3 . .
2.5 si (t) - ( ³ 4) - :
, (4)
aci, asi , n , si (t).
, (4), , A (t). , A (t) , , , , . 1. - - (3).
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2.6 - - ( ³ 4) , , (4), . (. 3). , y .
- (4) :
(5)
-4:
00 j0 = 135 (a 0 = as 0 = );
01 j1 = 45 (ac 1 = as 1 = );
10 j2 = 225 (ac 2 = as 2 = );
11 j0 = 315 (ac 3 = as 3 = ).
2.7 (2) (4) : n = log2 M - ai si ( ai, si = 0); - , ; ai (t) si (t) ; .
2.8 -2 , :
(6)
D f ;
, .
A (t) - , j0 = j1 = 0. , s 0(t) s 1(t):
. (7)
, (6) ,
(8)
, k = 1, .. D f = 0,5/ T. -2
, (9)
+ s 1(t), s 0(t).
(9) , cos2p f 0 t, p/2.
-2 () :
1. (6) A (t) - .
2. D f = 0,5/ T.
3. .
: cos2p f 0 t , . - dk (k ): 1 dk = 1, 0 dk = 1. Dj(t) t = n + D t
. (10)
- dk pD f D t. b (t) = {1, 0, 0, 1} . 4 Dj(t) .
, (11)
Dj(t) , (10).
s (t) :
, (12)
I (t) = cosDj(t) ;
Q (t) = sinDj(t) .
b (t) = {1, 0, 0, 1} . 4 . s (t) .
. (13)
(13) . 5. ï f f 0ï 1/(f f 0)2. F (13),
F = 1,5/ . (14)
2.9 , -2 , , A (t) . , s -2(t) 0 - D/2 0 + D/2. . 6 -2, , , , :
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. (15)
-2:
, (16)
-2 -2.
-2 - , D/2 .
3.1 ?
3.2 .
3.3 .
3.4 - , ‑ - .
3.5 - ? ?
3.6 - , - -2?
3.7 .
3.8 ?
3.9 , ?
4.1 " " [1, . 91...120; 3, . 164...168, 180...185; 4, . 103...112] . 6.
4.2 = 50 . s 1(t) 0 = 40 : - .
. , - .
,
( 4 , 4 ).
4.3 .
5.1 . 1.5 , , 1. , . 6. .
5.2 . , 128 + 10 N (N ) . : a = 1 ‑ 0,1 N.
5.3 -2 -4 . : -2; -. : , , . . . . -4.
.
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5.4 -2 -4 . , . 5.3, -2 -4. - - .
5.5 -2 . : ‑2; . : , , . .
5.6 . : -2; -. : , , . . ai (t) i bi (t). Dj(t) . 4.
-2, -2 .