LECTURE 3:
AMPLITUDE MODULATION
Communication EngineeringECEN 310
1-2
Lecture Outline
1-3
This lecture
Read Proakis and Salehi, Chapter 3
1-6
Modulation options
1-9
AM in pictures
1-10
4 variants of AM
1-13
Time domain AM signal
1-14
Phasor view of AM signal
1-15
Phasor view of AM signal
1-16
Phasor view of AM Signal
1-21
AM Modulation Index
1-22Envelope detection is not for
overmodulation
1-25
AM power efficiency
1-27
Envelope detection
1-28
Practical demodulation of AM signal
1-32
Can’t use envelope detection!
1-36
DSB-SC synchronous demodulation
1-42QAM – quadrature carrier
multiplexing
1-43
Features on QAM
1-44
Orthogonality
1-45
Orthogonality
1-46
Spectral lines for Sin and Cos
1-55
Hilbert transform
1-68
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