Communication Interview Questions and Answers (Topic Wise)

Introduction to Analog Communication System Questions and Answers

Q.1. What is meant by radio communication?

Ans. It is the type of communication that uses free space as a communication medium. The signal is transmitted in the form of electromagnetic waves.

Q.2. What are the various transducers used in communication systems?

Ans. Microphones, loudspeakers, TV camera tubes (to convert light into an electrical signal), and picture tubes are some of the transducers used in communication systems.

Q.3. What do you understand by the term baseband signal?

Ans. The electrical equivalent of the original message signal (i.e., sound, picture, computer data) is called a baseband signal.

Q.4. List the drawbacks of baseband transmission.

Ans. (i) Excessively large antenna heights (ii) Signals get mixed up (iii) Poor quality of reception (iv) Short-range of communication (v) Multiplexing is not possible.

Q.5. Define a communication channel and name different types of communication channels.

Ans. The communication channel is the medium used for the transmission of an electronic signal from one place to the other place. Communication channels can be conducting wires, cables, optical fibers, or free space.

Q.6. Why is modulation used?

Ans. Modulation is used for its following advantages: (i) Reduction in antenna height (ii) Avoids mixing of signals (iii) Increases the range of communication (iv) Multiplexing is possible (v) Improves quality of reception

Q.7. What is the channel bandwidth for TV transmission in India?

Ans. 7 MHz.

Q.8. What is the function of a carrier in a modulation system?

Ans. The carrier is supposed to carry the message signal or information from the transmitter to the receiver.

Q.9. Define the bandwidth of a baseband signal.

Ans. The bandwidth of a baseband signal is defined as its frequency range.

Q.10. What is meant by line communication?

Ans. Line or wire communication is the type of communication where the transfer of signal takes place through mediums such as wires, cables, or optical fibers (i.e., physical connection).

Q.11. What are the bandwidths of the following baseband signals? (i) TV signal (picture), (ii) Voice signal (Telephony), (iii) Music signal

Ans. (i) 5 MHz, (ii) 3100 Hz, (iii) Approximately 15 kHz

Q.12. What is meant by channel bandwidth?

Ans. The channel bandwidth may be defined as the range of frequencies in which a communication channel can allow the signal to travel with uniform attenuation and zero phase change (ideally). Signal distortion can take place if the channel bandwidth is not adequately large.

Q.13. Name the communication channels used for the following systems: (i) Cable TV Networks, (ii) TV and radio broadcasting, (iii) Satellite communication, and (iv) Closed-circuit TV (CTV).

Ans. (i) Shielded coaxial cable or optical fiber, (ii) Free space, (ii) Free space, (iv) Shielded coaxial cable.

Q.14. List different types of analog modulation systems.

Ans. Amplitude modulation (AM), frequency modulation (FM), and phase modulation (PM) are the types of continuous-wave analog modulation systems whereas PAM, PWM, and PPM are the pulse analog modulation systems.

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