Specifications

X(f) = - [-(6(7
+
19000 )
+
b(f - 19000 )) +-(6(f
+
21000 )
+
6(f - 21000 ))]
4 2 2
Q: What is the power of the DSBSC AM signal?
P = - A] - (0.5) (l
2
) = 0.5
2
Q: If the output of the envelope detector was passed through a BPF centered at
21 Khz, what type of output would we see? Sketch the output. What would the
frequency representation be? What would the power be?
A: The output would be Single Sideband centered at 2IK:
5K 10K 15K 20K
X(f) = -(&(/"+ 21000 )
+
b(f - 21000 ))
8
P = — Al = .25 l
2
= .25
2a) Q: How do the tones differ? What does this tell you about the quality of this
detector?
Lab 3 Solutions Page 4
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