The purpose of communication system is to transmit an information bearing signal, from a source, located at one point, to a user (destination) , located at another point .
The source we used two type of signals called analog or digital signal.
Analog Signal
Analog Signal is that type of signal which varies smoothly arid continuously with time.
This means that analog signals are defined for every value of time and they take on continuous values in a given time interval.
The signal depicted in figure is an analog signal.
For example, the temperature or the atmospheric pressure around us are example of analog signal.
Their value may vary over a continuous range and may assume an infinite number of possible value.
The analog message signal may be obtained from sources such as speech, video shooting, etc...
In analog communication the analog message signal modulates some high carrier frequency inside the transmitter to produce modulated signal.
This modulated signal is then transmitted with the help of a transmitting antenna to travel trough the transmission channel.
At the receiver this modulated signal is received and processed to recover the original message signal.
All the AM FM radio transmission and TV transmission are example of analog transmission system.
For example, the temperature or the atmospheric pressure around us are example of analog signal.Their value may vary over a continuous range and may assume an infinite number of possible value.The analog message signal may be obtained from sources such as speech, video shooting, etc...In analog communication the analog message signal modulates some high carrier frequency inside the transmitter to produce modulated signal.This modulated signal is then transmitted with the help of a transmitting antenna to travel trough the transmission channel.At the receiver this modulated signal is received and processed to recover the original message signal.All the AM FM radio transmission and TV transmission are example of analog transmission system.