Digital Signal Processing Reference
In-Depth Information
equivalent-length rectangular window;thisisdisplayedinFigure7.7fora
17-point window (values are normalized so that both frequency responses
are equal in
0). Filters designed with a triangular window therefore
exhibit a much wider transition band.
ω
=
l
g
r
,
y
i
d
.
,
©
,
L
s
18
15
12
9
6
3
0
-3
0
π/
4
2
π/
4
3
π/
4
π
Figure 7.7
Fourier transform of the 17-point rectangular window (gray) vs. an
equal-length triangular window (black).
1.0
0.5
−
40
−
30
−
20
−
10
0
10
20
30
40
Figure 7.8
Hamming window (
N
=
32 ).
1.0
0.5
−
40
−
30
−
20
−
10
0
10
20
30
40
Figure 7.9
Blackman window (
N
=
32 ).
