PRACTICAL MATLAB® FOR ENGINEERS PRACTICAL MATLAB

88 Practical MATLAB® Applications for Engineers

Binary information signal ASK signal

4

3

2

1

0

Amplitude

Amplitude

Amplitude

Amplitude

0 1 234

time

4

2

− 2

− 4

0

0 1 234

time

PSK signal

1

0.5

−0.5

− 1

(^0) 0.5 1
0
1.5
time
FSK signal
1
0.5
−0.5
− 1
0 1
0
2 3 4
time
FIGURE 1.74
Plots of ASK, FSK, and PSK telecommunication signals for a binary information signal of Example 1.18.
Information signal: 3cos(5t)
6
4
2
0
− 2
− 4
− 6
Amplitude
Amplitude
0123
Amplitude
Amplitude
Carrier signal: cos(50*t)
1.5
1
0.5
0
−0.5
− 1
−1.5
0
0 0.5 1 1.5 2
0.1 0.2 0.3 0.4
Angle Modulated signal
time
6
4
2
− 2
− 4
− 6
0
time
time
AM (Amplitude Modulated) signal
6
4
2
0
− 2
− 4
− 6
0123
time
FIGURE 1.73
Plots of standard analog telecommunication signals of Example 1.18.
Example 1.19
Given the following time functions:
f 1 (t) = cos(2t) + 2 sin(3t)
and
f 2 (t) = 10 sin(2t)e−t/π
over the range 0 ≤ t ≤ 2 π.