1 | P a g e
2 | P a g e ANALOG COMMUNICATION Modulation It is the process of placing the message signal over some carrier signal to make it suitable for transmission. Need for Modulation: 1. Size of antenna required for receiving the wave is reduced if signal is transmitted at high frequency. 2. Many number of signals can be transmitted simultaneously by selecting the carriers of different frequencies. 3. The interference of noise and other signals can be reduced by changing the frequency of transmission. 4. Integration of different communication system is possible. Amplitude Modulation Amplitude Modulated Signal: AM may be defined as a system in which the maximum amplitude of the carrier wave is made proportional to the instantaneous value (amplitude) of the modulating or base band signal Frequency spectrum of AM wave: A min – minimum amplitude
3 | P a g e Power Relations in AM wave: Maximum power dissipated in AM wave is P AM = 1.5 P c
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- Summer '16
- Jam Adam Scalin