Материал: 10
10.
FFT - Fast Fourier Transform
FÄ FÄ |
1 |
Re iIm |
R |
R R |
~ N2 |
, S cosi |
sin |
S |
T ~ Nlog2 N
GoodIS
A C C 
B Wk |
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W0 |
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W 1 |
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W0 |
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N=16. |
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W 4 |
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13 |
W0 |
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W 4 |
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S
0
S
6
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S0 |
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W0 |
S8 |
W0 |
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W0 |
W 4 |
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W 2 |
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W 4 |
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W 4 |
W 6 |
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W 1 |
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W 2 |
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W 2 |
W 5 |
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W 3 |
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W 6 |
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W 6 |
W 7 |
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n 0..3 |
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S0 |
1+i0 |
0 |
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S0 |
S1 |
0+i1 |
0 |
W0 |
0 |
S2 |
S2 |
-1+i0 W0 |
2 |
K |
4 |
S |
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1 |
S3 |
0-i1 W0 |
2i W 1 |
0 |
S3 |
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L |
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S1 
LW 1
K
L
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3 |
S1 |
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N 4 |
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S2 |
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T 
o 
N log2 N
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1 t 
F
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S1 |
W0 |
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S2 |
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W0 |
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W0 |
W2 |
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W0 |
W0 |
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W1 |
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W2 |
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W0 |
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W0 |
W2 |
W3 |
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W0 |
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W4 |
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W0 |
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W2 |
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W4 |
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W0 |
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W6 |
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W0 |
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W1 |
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W2 |
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W0 |
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W3 |
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W4 |
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W4 |
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W |
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W5 |
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W |
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W6 |
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W0 |
W |
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W4 |
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W7 |
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W |
4 |
W |
6 |
15 |
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