Сигнали и Системи, Готова

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Сигнали и системи

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, 2014

1.21.1 22. 62.1 62.2 62.3 93. 143.1 143.2 153.3 363.3.1 1: 363.3.2 2: 384.BIBO 394.1 415. :43

1. . . . . ( ) . ( ) ( ). . - . , .

1.1 , : . , . , . ( ), (), ( ).

. . , : s (x, t) ( ). , , 0. 1.1 ( 1.1). , . - , . 1.2, . . , .. , , . , , , : , . , : s (x) = (r (x) , g (x) , b (x))T . , , . , , .

1.1: . ( )

. ( , ).

Ascii

1.3: ASCII . .. 7- ( ?); ASCII 8- . (-16). , .

, . , . ASCII , , - . , ASCII 97 65. 1.3 .

2.

2.1 , . . , , , (DSP). , . , , .. .

2.2

, . , - - . , .

() (), . H (kf (t)) = kH (f (t))

2.1:

2.2: H (f1 (t) + f2 (t)) = H (f1 (t)) + H (f2 (t)) (2.2) () . , :H (k1f1 (t) + k2f2 (t)) = k2H (f1 (t)) + k2H (f2 (t)) (2.3)

: . H (f (t)) = y (t), H

H (f (t T)) = y (t T) (2.4)

2.3: . .

, , .

; , . , . ; , , . . () , .

. . , , x (t) y (t) |y (t) | _ My < 1 (2.5) |x (t) | _ Mx < 1 (2.6)

Mx My t. , .. ( ) , .

2.3

, , , , , .

2.4: ) ... ) ... t0, y (t0), t0.

2.5 () , L y , () . . , . () , () . . , x y , .

, .

2.8: () t () , 10 . , , , .. () 10 .

, x(t) x(t t0) TI. , x(t) x(t t0) . x(t t0) t0. , . . , .

(LTI) LTI . LTI , . .

2.6: () , () . .

2.7: () , () .

2.9: . () , (), .

2.10: LTI

LTI LTI , . .

LTI LTI , .

, . t0 , . : h(t) t t1 > 1. . t1 .

, . . , f(t) t1 > 1 t2 < 1. . , f(t) :

2.21: () ()

. , , . , . . , . . , . , , . , . , , . , . , : . , , .

2.22: . .

s (n), n = {. . . ,1, 0, 1, . . . }. . . n=m.

2.23: .

2.24:

. (2.9) . f . . (2.10)

, : (2.11) , 2.23, . s(m) m (n-m), .

(2.12) . . . , .. , , , . , , .. .

. , . {a1, . . . , aK}, . , , , . , , . , , , .

. , .

. , :

(2.13) , w , . wt . , , , :

(2.14)

2.25: =2, w=2 =0

, :

f(t)= (2.15) , :s= , :(f(t)= (2.16) . , . - , < 0 - , > 0

. , , , , t=0. , (t)

2.26: () ()

:

(2.17)

- - , :

(2.18) , , . . , , .

. : (2.19)

2.27: () ()

2.28:

: , , . : , : (2.20)(2.21) . , : . (2.22)

e , (2.23) , t , , = jw. , : (2.24)

, . , . , , . , , , = +jw, : (2.25) : (2.26) , , :. (2.27) : (2.28) (2.29)

, . , : (2.30) nT .

, : (2.31)(2.32) (2.33)

2.29: . , t=0. () , . () , . () , .

1 -1. , . /, w .

2.30: - . , , .

(- )

s(n) n0 s ( n - n0 ), n - > 0. , . , :

: (2.34) , . S (x (n)) = y (n), S (x (n- n0)) = y (n- no).

, . , . (2.36), y (n) y (n l), l = {1, . . . , p}, x (n). q . , , . , , . . MATLAB 1000 :

y(0), y(-1), ..., . , . , . , : . , . : . : .

, . , . .

, , . , , . . , , 1. (2.41) (t).

2.34: .

2.35: , . , . .

. (2.42)

= 2.43) . (t - T) (t), f(t) . , . , . , .

. . u(t) .

( )

2.36:

(2.44) k s [k] k [n k], , . (2.45) .: 2.45 .

LTI , . . : (t) [n] .

3.3

. , . ? ? : , MATLAB. , .

2.31 1: p = 1 q = 0.y(n) = ay (n-1) +bx (n)(2.37) , y (n 1) . : x (n) = (n). , n=0. y(0) = ay (-1) +b(2.38) y(-1)? , . , y (1) = 0, y (0) = b. y(n)= ay (n-1) + b (n)(2.39) . b , . , b. , , , . , . 1, . =1, . , -1, . =1, , b b. |a| > 1, , , .

2.32: , .

, . , n . , . 1, , 1 . . , n (, .), 1, b=1. , . , |a| = 1 b .

2:

y (n + 1) x (n + 1), . ? .. ?: , . , .

2.3: . :(2.40) , 1q n = {0, . . . , q 1}, .

2.33: . , . 2.33 q 1q. . , q . (q=7).

4. BIBO BIBO , . BIBO . , . , . , .

2.37:

, . , . LTI h(t) BIBO , (2.46)

, h (n), . : (2.47)

4.1 . jw . .

2.38: () - . () - .

- - , . , jw , .

2.39: 9) ()

5. :[1] "Fundamentals Of Control Theory (Ch12 Of Mems Handbook)", Bill GoodwineUniversity of Notre Dame.[2] "Signals and Systems", Richard Baraniuk.

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