.
() (correlation function, CF). , s(t), t:
Bs(t) = s(t) s(t+t) dt. (2.4.1)
, t. , , t = 0 ( 1):
Bs(0) = s(t)2 dt = Es.
. t = t-t (2.4.1):
Bs(t) = s(t) s(t-t) dt = s(t-t) s(t) dt = Bs(-t).
, t. +t (2.4.1) , t s(t+t) t. 0-, , . , .. (2.4.1) s(t-t):
Bs(t) = s(t) s(t-t) dt. (2.4.1')
t , , , :
= 0.
. (0,) , . .
t , 0≤t≤T t . :
Bs(t) = A2 dt = A2(T-t).
, -T≤t<0 0 -t. :
Bs(t) = A2 dt = A2(T+t).
|t| > T ( ).
, :
Bs(t) = .
, :
Bs(t) = (1/) s(t) s(t-t) dt.
t=0 , . . , s(t) = A cos(w0t+j0) T=2p/w0 :
|
|
Bs(t) = A cos(w0t+j0) A cos(w0(t-t)+j0) = (A2/2) cos(w0t).
, , .
, [a, b], [a, b]:
Bs(t) = s(t) s(t+t) dt. (2.4.2)
, :
Bs(t) = . (2.4.2')
, ( ):
rs(t) = cos j(t) = ás(t), s(t+t)ñ /||s(t)||2.
() (cross-correlation function, CCF) ( ), (2.4.1), , , t:
B12(t) = s1(t) s2(t+t) dt. (2.4.3)
t = t-t (2.4.3), :
B12(t) = s1(t-t) s2(t) dt = s2(t) s1(t-t) dt = B21(-t)
, , t = 0. . 2.4.1, 0.5 1.5. (2.4.3) t s2(t) ( s1(t) s2(t+t)).
. 2.4.1. . |
t=0 B12(t)=0. 12(t) s2(t) t=1, s1(t) s2(t+t). B21(-t) s1(t) t, B21(-t) ( t=0) B12(t), . . 2.4.2 .
. 2.4.2. . |
, t , t (2.4.3) .
, , , .
( ):
rsv(t) = cos j(t) = ás(t), v(t+t)ñ /||s(t)|| ||v(t)||. (2.4.4)
-1 1.