文档文本内容
- https://51jobs.taobao.com/ galerjim
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/ / offer
1- https://51jobs.taobao.com/ galerjim
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/ / offer
2- https://51jobs.taobao.com/ galerjim
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0 0
f(t t )* (t t ) f(t t t ) t ,t ,t
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/ / offer
3- https://51jobs.taobao.com/ galerjim
t
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dn dn f (t) dn f (t)
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dtn 1 2 dtn 2 1 dtn
t t t
5 [f ( )* f ( )]d [ f ( )d ]* f (t) f (t)*[ f ( )d ]
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6 f (t –t )* f (t –t ) = f (t –t –t )* f (t) = f (t)* f (t –t –t ) = f(t –t –t )
1 1 2 2 1 1 2 2 1 2 1 2 1 2
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/ / offer
4- https://51jobs.taobao.com/ galerjim
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F( ) F( ) F( ) ej ( )
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/ / offer
5- https://51jobs.taobao.com/ galerjim
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/ / offer
6- https://51jobs.taobao.com/ galerjim
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/ / offer
7- https://51jobs.taobao.com/ galerjim
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fs 2fm Ts 1/(2fm)
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F(s) f(t)e stdt
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/ / offer
8- https://51jobs.taobao.com/ galerjim
df(t)
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0 s
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f (t)*f (t) F (s)F (s)
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7 F(s) F(s) 1
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/ / offer
9- https://51jobs.taobao.com/ galerjim
Y (s) H(s)F(s)
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h(t) H(s) H(s) F(s)
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H(s)
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D(s) a sn a sn 1 a s a
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/ / offer
10- https://51jobs.taobao.com/ galerjim
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35
1 (n)
1, n 0
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x(n) x(k) (n k)
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f(n) f (k)f (n k)=f (n)*f (n)
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k
/ / offer
11- https://51jobs.taobao.com/ galerjim
(1) f n f n f n f n
1 2 2 1
(2) f n f n f n f n f n f n
1 2 3 1 2 3
(3) . f n f n f n f n f n f n f n
1 2 3 1 2 1 3
f(n)* (n) = f(n) f(n)* (n– n ) = f(n– n )
0 0
n
f(n)* (n) = f(k)
k
f (n – n )* f (n – n ) = f (n– n – n )* f (n)
1 1 2 2 1 1 2 2
39
y (n) f(n)*h(n)
zs
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F(z) f(n)z n f((kk)) z
n
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z 1
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ak (k) |z| |a|
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1
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z f(k- F(z) + f(-2) + f(-1)z
k k
2 a (z ) a f F(z/a)
/ / offer
12- https://51jobs.taobao.com/ galerjim
3 f (k)*f F (z)F (z)
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y (n) h(n) f(n) f(n) h(n)
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zs
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H(z)
/ / offer
13
