This set of Antennas Multiple Choice Questions & Answers (MCQs) focuses on “Radio Wave Propagation – Structure of Troposphere”.
1. What is the frequency used for tropospheric scatter propagation?
a) Above 30GHz
b) Above 30MHz
c) Above 300MHz
d) Above 300GHz
Explanation: Tropospheric scatter propagation is used for UHF and microwaves. So it is used at frequencies above 300MHz. Sky wave propagation is used at frequencies above 30MHz (VHF).
2. Which of the following scattering occurs through the fine layers in the troposphere?
a) Forward Scatter propagation
c) Space wave
Explanation: Forward scatter propagation or Tropospheric propagation occurs at frequencies above 300MHz through the fine layers or blobs in the troposphere. UFH and microwaves propagate much beyond the LOS through forward scattering in tropospheric irregularities.
3. Height of the troposphere ranging from earth surface is up to _____
Explanation: The Troposphere portion of earth extends up to 15km from the earth surface. Ionosphere from 50 to 400km and Outer atmosphere extends above 400km.
4. At which region of the troposphere the temperature remains constant throughout the narrow belt?
b) Region of change
c) Region of calm
Explanation: At Tropopause starts after the top of troposphere and ends at stratosphere. Above critical height called Tropopause the temperature remains constant throughout belt and increases thereby. Entire belt of troposphere is called Region of change.
5. The lowest layer in the structure of atmosphere extends to a distance of _____km from earth surface
Explanation: The lowest layer of the atmosphere is troposphere. So it ranges up to 15km from the surface of the earth. The gas components remain almost constant in this region.
6. The actual height of troposphere is least at ____
c) both equator and poles
d) other composition other than poles and equator
Explanation: The actual height of troposphere is least at poles and maximum at equator. At other compositions it is almost remains same. The entire belt of troposphere is called Region of change.
7. Which of the following is a property of troposphere?
a) Temperature decreases with increase in height
b) Temperature increases with increase in height
c) Gas components don’t remain in constant percentage with increase in height
d) Water vapor components remain same with height
Explanation: The property of troposphere is that temperature decreases with increase in height. Gas components remains in constant percentage with increase in height but water vapor components decrease with increase in height.
8. Which of the following is the nearest region from the earth surface in the atmosphere?
d) Outer atmosphere
Explanation: Troposphere is the lowest layer and nearest to earth surface in the atmosphere ranging up to 15km. Stratosphere lies at 50 to 90km and up to 400km ionosphere. Above 400km is the outer atmosphere.
9. The region between the top of troposphere and start of stratosphere is called ____
d) region of calm
Explanation: The region between the top of troposphere and start of stratosphere is called Tropopause. Stratopause is also known as region of calm and ranges from 20 to 70km.
10. Troposphere scatter propagation is used for point to point communication
Explanation: Since the troposphere propagation takes at 2- 15km from earth surface there is a possibility for great attenuation. It is used for point to point communication.
Sanfoundry Global Education & Learning Series – Antennas.
To practice all areas of Antennas, here is complete set of 1000+ Multiple Choice Questions and Answers.