Question

Draw a block diagram of a generalized communication system. Write the functions of each of the following.
a) Transmitter
b) Channel
c) Receiver

Answer 1

Hint: A communication system consists of various sending and receiving stations. The system that transmits the signal is called a transmitter. The signal travels through the channel. The signal is received by the receiver.

Detailed step by step solution:

This figure shows the block diagram of a generalized communication system. We have a source of information which generates a message signal which needs to be transmitted to the user of the information. This communication between the information source and the user is attained through the communication system.

Transmitter: The message signal is first sent to a transmitter. The function of the transmitter is to dispatch the message signal. But before sending it, modulation is done using a modulator inside the transmitter. The message can be modulated in three ways: amplitude modulation (AM), frequency modulation (FM) and pulse modulation (PM). After modulation, the signal is sent over the communication channel.

Communication channel: The message travels from transmitter to receiver through a communication channel since the message needs to be sent over a distance. The communication channel can be of many types like through atmosphere or optical cables.

Receiver: The transmitted signal is received at the receiver. The purpose of the receiver is to receive and de-modulate the message signal using a demodulator inside the receiver. The message is decoded and then sent to the user of information.

Note: When a signal is travelling through the communication channel, it can encounter external noise which is an undesired random signal that can distort the signal. Due to this the signal is also filtered of noise at the receiving end.