Digital Signal Processing Reference
In-Depth Information
FIGURE 6.11. Sixteen-point radix-4 FFT flow graph using DIF.
The intermediate output sequence after stage 1 is shown in Figure 6.11. For
example, after stage 1:
[
() +
() +
() +
()
]
=+++ = Æ ()
x
0
x
4
x
8
x
12
W
0
1
1
0
0
2
x
0
[
() +
() +
() +
()
]
=+++ = Æ ()
0
x
1
x
5
x
9
x
13
W
1
1
0
0
2
x
1
M
M
[
() -
() -
() +
()
]
=---=-Æ ()
x
0
jx
4
x
8
jx
12
W
0
1
j
0
0
1
j
x
4
M
M
[
() -
() +
() -
()
]
()
x
3
x
7
x
11
x
15
W
6
0
x
11
[
() +
() -
() -
()
]
=+-- =+Æ¢ ()
x
0
jx
4
x
8
jx
12
W
0
1
j
0
0
1
j
x
12
M
M
[
() +
() -
() -
()
]
[
] -
(
)
x
3
jx
7
x
11
jx
15
W
9
=+--
1
j
0
0
W
1
Æ ¢ ()
=-
1 307
.
-
j
0 541
.
x
15
For example, after stage 2:
() =+
(
) +
(
) +-
(
) +-
(
) =-
X
3
1
j
1 307
.
-
j
0 541
.
j
1 414
.
1 307
.
-
j
0 541
.
1
j
1 496
.
and
Search WWH ::




Custom Search