Elements / Components of Communication system?
The system by which information are transmitted at one place and received at another distant place is called communication. The set-up used for the purpose of communication is called a communication system. It may be Electrical, Electronic or optical phase system. Every communication system has three essential elements, namely (a) transmitter, (b) channel and (c) receiver.
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| Element of Communication System |
(i) Transmitter
Transmitter is an extremely important equipment which convert the information signal into a suitable form for transmission through the channel. The important component of a transmitter are microphone, audio amplifier, oscillator and modulator.
(a) Microphone
microphone is a device which converts sound waves into electrical waves. When the speaker speaks or a musical instruments is played the varying air pressures on the microphone generates an audio electrical signals which corresponds in frequency to the original signal.
(b) Audio amplifier
The audio signal from the microphone is quite big and requires amplification. This job is accomplished by cascaded audio amplifiers.
(c) Oscillator
An electronic device that generates oscillations of desired frequency is known as a oscillator. The function of oscillator is to produce a high frequency signal called a carrier wave.
(d) Modulator
The amplified audio Signals and carrier wave are fed to the modulator. Here, the audio signal is superimposed on the carrier waves in a suitable manner. The resultant waves are called the modulated waves or radio waves and the process is called modulation.
(ii) Communication Channel/ Medium
The channel is the physical medium that connects a transmitter to a receiver. The message signal, transmitted by transmitter, reaches the receiver through a channel. Depending upon the nature of communication systems, a channel may be in the form of wires or cables connecting the transmitters and receivers or it may be wireless. When a transmitted signal is propagated along the channel, it may get distorted due to imperfection of the channel and we say that noise is added up to the transmitted signal.
(iii) Receiver
It is a setup which first receive the transmitted signal from the communication channel and then convert back to their original form. This process is called the modulation or detection. This original signal is amplified by amplifier and then transmitted to the sound speaker which convert the signal into information of sound wave.
Basic mode of communication
There are two basic modes of communication. These are,
Point-to-Point Communication mode:- In point to point communication mode, communication takes place between single transmitter and a single receiver. Telephone and cell phone are examples of point-to-point mode communication system.
Broadcast communication mode:- In the broadcast mode of communication, there are a large number of receivers corresponding to a single transmitter. Radio and television are examples of Broadcast mode of communication system.