Amplitude Modulation

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Amplitude Modulation

• Lecture 6
• Dr. Yossef Ben-Ezra

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Complex envelope, AM signal

• The complex envelope of an AM signal is given by
• The AM signal is represented by the equation

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Definitions

• If m(t) has a peak value of 1 and a peak
  negative value -1, the AM signal is said to be
  100 modulated.
• The percentage of positive modulation on an AM
  signal is
• The percentage of negative modulation on an AM
  signal is
• The overall modulation percentage is

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AM signal waveform
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AM - continue
The normalized average power of the AM signal is
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Modulation efficiency
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PEP and spectrum of AM signal

• Normalized peak envelope power (PEP) of the AM
  signal
• The voltage spectrum of the AM signal is given
  by

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AM broadcast technical standards
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Double-sideband suppressed carrier