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Ionospheric Propagation MCQs

Practice Ionospheric Propagation MCQs with four options, answers and explanations for focused Electronics & Telecommunication Engineering revision.

Question 1
Antenna & Wave PropagationIonospheric Propagation

The ionosphere is important to HF communication because it contains?

  • AIonized particles capable of refracting radio waves
  • BOnly neutral particles with no electromagnetic effect
  • CA perfect metallic mirror
  • DNo free electrons
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Correct Answer: A. Ionized particles capable of refracting radio waves
Explanation: Solar radiation ionizes portions of the upper atmosphere, producing electrons and ions that affect radio-wave propagation.
Reference: Standard antenna and wave propagation: ionospheric propagation
Question 3
Antenna & Wave PropagationIonospheric Propagation

The D layer is particularly associated with significant absorption of?

  • ALower-HF and MF radio waves
  • BVisible light only
  • CAll microwave signals completely
  • DDC current
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Correct Answer: A. Lower-HF and MF radio waves
Explanation: Collisions in the lower ionosphere cause appreciable absorption, especially at lower radio frequencies.
Reference: Standard antenna and wave propagation: ionospheric propagation
Question 4
Antenna & Wave PropagationIonospheric Propagation

During daytime, the F region commonly separates into?

  • AF1 and F2 layers
  • BD1 and D2 only
  • CE1 and E2 only
  • DTwo tropospheric layers
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Correct Answer: A. F1 and F2 layers
Explanation: Under daytime solar ionization, the F region is commonly described as F1 and F2; they tend to merge at night.
Reference: Standard antenna and wave propagation: ionospheric propagation
Question 5
Antenna & Wave PropagationIonospheric Propagation

Virtual height of an ionospheric layer is the apparent reflection height inferred by assuming the radio wave?

  • ATravels at the speed of light along an equivalent straight path
  • BStops at the ionosphere
  • CTravels through a metallic cable
  • DHas zero propagation time
Report an error
Correct Answer: A. Travels at the speed of light along an equivalent straight path
Explanation: Virtual height is derived from propagation delay using an equivalent straight-line path assumption and is not necessarily the true physical layer height.
Reference: Standard antenna and wave propagation: ionospheric propagation