Antenna Fundamental Parameters MCQ

Antenna Fundamental Parameters MCQ

Antenna Fundamental Parameters MCQ, MCQ on Antenna Fundamental Parameters, Multiple Choice Questions on Antenna Fundamental Parameters, Antenna Fundamentals MCQ, Basic Antenna Parameters MCQ, Antenna MCQ, Engineering MCQ

objective questions on maxwell’s equations

Horn Antenna MCQ

Objective Type Questions

Q.1. The horn antenna was developed by

• J.C. Bose (1900, India)
• Maxwell (1800, USA)
• J.D. Kraus (1789, UK)
• None of these

Answer: J.C. Bose (1900, India)

Q.2. Directivity of an antenna is determined by

• Gain
• Impedance pattern
• Radiation pattern
• Efficiency

Answer: Radiation pattern

Q.3. Which is not a modern antenna?

• Dipole antenna
• Slot antenna
• Reflector antenna
• Lens antenna

Answer: Reflector antenna

Q.4. Power loss during power transformation through an antenna at distance R is proportional to (R^–2), whereas power loss during power transformation through a Tx line at distance R is proportional to

• (R^–2)
• (R²)
• e^–αR
• (e^–αR)²

Answer: (e^–αR)²

Q.5. Directive antennas are useful in point to point communication, whereas omnidirectional antennas are useful in

• Broadside situation
• Microwave ovens
• As a feed-in reflector
• None of these

Answer: Broadside situation

Q.6. Double polarized antennas enable the doubling of communication capacity by carrying separate information on orthogonal polarizations over the same physical link and at

• Different frequency
• Same frequency
• Both of these
• None of these

Answer: Same frequency

Q.7. A type of antenna acts as a funnel and directs the waves into the connecting waveguide.

This is the

• Horn antenna
• Slot antenna
• Reflector
• Lens antenna

Answer: Horn antenna

Q.8. Electrically small antennas

• High directivity
• Low input impedance
• High input reactance
• Low radiation efficiency

Answer: High directivity

Q.9. Resonant antennas

• Moderate gain
• Real input impedance
• Narrow bandwidth
• Finite reactance

Answer: Finite reactance

Q.10. Broadband antennas

• Wide Bandwidth
• Real input impedance
• Constant gain
• High reactance

Answer: Wide Bandwidth

Q.11. Quasi-fields vary with the distance as

• 1/r
• 1/r²
• r²
• None of these

Answer: 1/r²

Q.12. The distance at which far- and near-fields are equal is (λ/2π) is termed

• Radian sphere
• Radian distance
• Equi-distance
• None of these

Answer: Radian sphere

Q.13. Ohmic losses on an antenna are due to

• Antenna temperature
• Noise figure
• Noise temperature
• Noise sources

Answer: Noise sources

Q.14. The external noise picked up by the antenna is proportional to the antenna radiation resistance and it is larger than the noise arising from internal ohmic losses.

• True
• False
• Not known
• None of these

Answer: True

Q.15. The reactive part of input impedance (X_A) of an antenna represents power stored in the

• Near-field
• Far-field
• Both near and Far-field
• Quasi-field

Answer: Near-field

Q.16. The short dipole has a capacitive reactance, whereas an electrically small dipole has

• Inductive reactance
• Capacitive reactance
• Both inductive and capacitive reactance
• None of these

Answer: Inductive reactance

Q.17. Helix antenna provides complete

• Linear polarization
• Circular polarization
• Elliptical polarization
• Parallel polarization

Answer: Circular polarization

Q.18. In general, the value of AR is +ve for RHCP and –ve for LHCP. It is measured in dB, which is converted by using

• 10 log AR
• 10 log_e AR
• Both the above
• 20 log AR

Answer: 20 log AR

Q.19. An antenna has a directivity of 20 and radiation efficiency of 90%. What is its gain (dB)?

• 2.55 dB
• 12 dB
• 12.55 dB
• 90 dB

Answer: 2.55 dB

Q.20. A horn antenna has a half-power beamwidth of 29° in both the principal planes. What is the directivity in dB?

• 22 dB
• 45 dB
• 24 dB
• 17 dB

Answer: 17 dB