Digital Signal Processing Reference
In-Depth Information
9.1.
Determine which of the following discrete-time functions is different:
(a)
(b)
(c)
(d)
x
1
[n] = u[n] + u[-1 - n]
x
2
[n] = g
k=-
q
d[n - k]
x
3
[n] = u[n] + u[-n]
x
4
[n] = u[-n] + u[n - 1]
9.2.
The discrete-time signals in Figure P9.2 are zero except as shown.
(a)
For the signal
x
a
[n]
of Figure P9.2(a), plot the following:
(i)
x
a
[3n]
(ii)
x
a
[-n/3]
(iii)
x
a
[-n]
(iv)
x
a
[3 - n]
(v)
x
a
[n - 3]
(vi)
x
a
[-3 - n]
(b)
Repeat part (a) for the signal
x
b
[n]
of Figure P9.2(b).
(c)
Repeat part (a) for the signal
x
c
[n]
of Figure P9.2(c).
(d)
Repeat part (a) for the signal
x
d
[n]
of Figure P9.2(d).
x
a
[
n
]
x
b
[
n
]
3
3
2
2
•••
•••
1
1
•••
•••
1
234
2
1
0
6
5
4
3
2
1
0
5
6
7
n
6
5
4
3
1
234
5
6
7
n
1
1
2
2
(a)
(b)
x
c
[
n
]
4
x
d
[
n
]
3
3
2
2
•••
•••
•••
•••
1
1
1
1
3
0
0
4
3
2
2
4
5
6
n
6
5
4
3
2
1
1
234
5
6
7
8
n
1
1
2
2
(c)
(d)
Figure P9.2
9.3.
The signals in Figure P9.2 are zero except as shown.
(a)
For the signal
x
a
[n]
of Figure P9.2(a), plot the following:
(i)
2 - 3x
a
[n]
(ii)
2x
a
[-n]
(iii)
3x
a
[n - 2]
(iv)
3 - x
a
[n]
(v)
1 + 2x
a
[-2 + n]
(vi)
2x
a
[-n] - 4
(b)
Repeat part (a) for the signal
x
b
[n]
of Figure P9.2(b).
(c)
Repeat part (a) for the signal
x
c
[n]
of Figure P9.2(c).
(d)
Repeat part (a) for the signal
x
d
[n]
of Figure P9.2(d).
