Modulation by a Complex Sinusoid
Figure 9.12 shows the system diagram for complex
demodulation.10.2The input signal
is multiplied by a
complex sinusoid to produce the frequency-shifted result
![]() |
(10.8) |
Given a signal expressed as a sum of sinusoids,
![]() |
(10.9) |
then the demodulation produces
![]() |
(10.10) |
We see that frequency



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