Communication System
The word communication has been derived from Latin ward ―communis‖ which means common. Thus communication means sharing of ideas is common. It can be defined as exchange of facts, ideas, opinions or emotions between two or more persons to create a common ground of understanding.
Communication is the process of passing information & message from one person to another. It involves atleast two persons i.e. a sender & a receiver. The sender develops & transmits a message to the receiver. The purpose is to achieve common understanding between the sender & the receiver.
Man has constantly made endeavors to improve the quality of communication with other human beings. Languages and methods used in communication have kept evolving from prehistoric to modern times, to meet the growing demands in terms of speed and complexity of information.
Modern communication has its roots in the 19 and 20 century in the work of scientists like J.C. Bose, F.B. Morse, G. Marconi and Alexander Graham Bell.
In a communication system, the transmitter is located at one place, the receiver is located at some other place (far or near) separate from the transmitter and the channel is the physical medium that connects them. Depending upon the type of communication system, a channel may be in the form of wires or cables connecting the transmitter and the receiver or it may be wireless. The purpose of the transmitter is to convert the message signal produced by the source of information into a form suitable for transmission through the channel. If the output of the information source is a non-electrical signal like a voice signal, a transducer converts it to electrical form before giving it as an input to the transmitter. When a transmitted signal propagates along the channel it may get distorted due to channel imperfection. Moreover, noise adds to the transmitted signal and the receiver receives a corrupted version of the transmitted signal.
The receiver has the task of operating on the received signal. It reconstructs a recognisable form of the original message signal for delivering it to the user of information.
A transducer is a device that converts one form of energy to another. Usually a transducer converts a signal in one form of energy to a signal in another There are two basic modes of communication: point-to-point and broadcast. In point-to-point communication mode, communication takes place over a link between a single transmitter and a receiver. Telephony is an example of such a mode of communication. In contrast, in the broadcast mode, there are a large number of receivers corresponding to a single transmitter. Radio and television are examples of broadcast mode of communication.