Duduli

Communication system is a system which consist of transmitter, communication channel & receiver. →A block diagram of a generalised communication systemn is shown as below ★ Transmitter:- It consists of transducer/signal generators,modulators, Amplifier & transmitting antenna. ★ Communication channel:- The physical path between the transmitter & receiver is known as communication channel. ★ Receiver:- Its main function involves picking up the signals, demodulating, amplifying & displace the original message signal.

Answer:- A region of earth's atmosphere inbetween stratosphere and mesosphere capable of absorbing harmful radiations from sun.

Answer:- Radiation of electro-magnetic waves into the space is done with the help of a long conductor called an aerial or antenna.

Answer:- It is a circuit whose output is one of the two voltage levels depending on whether the input is greater or less than a pre-set threshold level.

Answer:- This is a device which sends a binary data in which a binary 1 is represented by a positive voltage for the duration of complete symbol period and binary 0 is represented by zero volt.

Answer:- The stations, which become inaccessible to ground waves due to the curvature of earth, can receive waves after reflection from the ionosphere.These waves are called sky waves.

Answer:- Modulation is the process of superimposing the signal to be transmitted on other wave of high frequency called carrier wave so that it can be transmitted to larger distances.