Digital Signal Processing Reference
In-Depth Information
h
[
k
]
1/3
•••
•••
3
2
1
0
1
2
3
k
6
4.5
x
[1
k
]
3
•••
•••
3
2
1
0
1
2
3
k
(d)
h
[
k
]
1/3
•••
•••
2
1
0
1
2
3
k
6
4.5
x
[2
k
]
3
•••
•••
2
1
0
1
2
3
k
(e)
y
[
n
]
4.5
3.5
2.5
2
1
1
0
1
2
3
4
5
6
n
(f)
Figure 10.4
(cont.)
We now plot the factor First, we change the time variable from
n
to
m
in Figure
10.4(a) to yield
x
[
m
], to facilitate the plotting. Recall that in the convolution sum,
n
is consid-
ered constant. Now, from Section 9.2,
x[n - k].
x
t
[k] = x[m] ƒ
m=n-k
= x[n - k].
Thus,
m = n - k Q k = n - m.
