Digital Signals and Systems - Digital Signal Processing: Fundamentals and Applications - page 81

3.6. Given the digital signals xðnÞ in Figures 3.24 and 3.25 , write an expression for each digital
signal using the unit-impulse sequence and its shifted sequences.

x ()

4

3

2

2

1 1

1

1

n

1 0 1 2 3 4 5

FIGURE 3.24

The first digital signal in Problem 3.6.

x ()

1

n

5

1 0 1 2 3 4

1

FIGURE 3.25

The second digital signal in Problem 3.6.

3.7. Sketch the following sequences:

a. xðnÞ¼ 2 dðn þ 3 Þ 0 : 5 dðn þ 1 Þ 5 dðn 2 Þ 4 dðn 5 Þ
b. xðnÞ¼ 2 dðn þ 2 Þ 2 dðn þ 1 Þþ 5 uðn 3 Þ

3.8. Given the digital signals xðnÞ in Figures 3.26 and 3.27 , write an expression for each digital
signal using the unit-impulse sequence and its shifted sequences.

x ()

4

3

2

1

n

1 0 1 2 3 4 5

FIGURE 3.26

The first digital signal in Problem 3.8.