(→Amplitude Modulation) |
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c(t) | c(t) | ||
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| + | x(t) : "information bearing signal" | ||
| + | |||
| + | c(t) : "carrier" | ||
| + | |||
| + | There are two important types of carriers which are "complex exponential" and "sinusoidal" | ||
| + | |||
| + | |||
| + | == Complex expenetial == | ||
| + | |||
| + | <math>c(t) = e ^{j(\omega_c t + \theta_c)}</math> | ||
| + | |||
| + | <math>\omega_c = </math> Frequency of carrier | ||
| + | |||
| + | <math>\theta_c = </math> Phase of carrier | ||
Revision as of 06:11, 17 November 2008
Amplitude Modulation
Def:Amplitude modulation (AM) is a method of impressing data onto an alternating-current (AC) carrier waveform.The highest frequency of the modulating data is normally less than 10 percent of the carrier frequency.
$ x(t) \longrightarrow\otimes\longrightarrow y(t)=x(t)c(t) $
$ \uparrow $
c(t)
x(t) : "information bearing signal"
c(t) : "carrier"
There are two important types of carriers which are "complex exponential" and "sinusoidal"
Complex expenetial
$ c(t) = e ^{j(\omega_c t + \theta_c)} $
$ \omega_c = $ Frequency of carrier
$ \theta_c = $ Phase of carrier
