In today’s world the whole Earth has turned into a global village,by the different processes of communication. So, we can say that with the advancing world and technology “Communication” plays a vital role in every aspect of life.
The apt and appropriate definition of “Communication” is that it is a process by which we can share or express our views,opinions,ideas,knowledge and many more things.Its involves various process.
1. Ideation: it is a process of thinking and idealizations in the form of thought and views.
2.Source of information: It is the transmitter which convert the bits,symbols and numerals in the form of electrical signals.
Source of information: Its is the block which deals which the information gathered.
Source coder: Its converts the bits,symbols,numerals in the form of electrical pulse.
Channel coder: Through differnet channels we send our data. At channel end “Noise” is introduces and corrupts the message signal.
Modulator: A Modulator modulates the signal by changing the characteristics of carrier signal in accordance with the message signal.
Demodulation: It demodulates the signal back to its original form by various methods.
Destination: It is the recevier side at which our message is retrieved
It is a process by which we change the characteristics features like frequency,phase and amplitude of the carrier signal in accordance with the message signal.Its is like imposing a low carrier signal onto the high carrier.
Need for Modulation:
1.To get the small bandwidth.
2.To reduce the Noise level of the signal
3.Height of Antenna
4. To increase the Signal to noise ratio.
5. Power requirement is less.
Different types of Modulation techniques:
There are basically three types of Modulation technique which are as folllows:
Amplitude Modulation:It is a process by which we change the characteristics of carrier signal with accordance of amplitude of message signal.
Frequency Modulation:It is process by which we change the characteristics of carrier signal with accordance of frequency of the message signal.
Phase Modulation: It is a process by which we change the characteristics of carrier signal with accordance of phase angle of the message signal.