Frequently Asked Questions On Antenna Theory With Answers -15.



This page contains basic questions and short notes on some of the keywords on antenna theory:


71) List the applications of helical antenna?

The applications of helical antenna are:
  • It became the workhouse of space communications for telephone, television and data, being employed both on satellites and at ground stations.
  • Many satellites including weather satellites, data relay satellites all have helical antennas.
  • It is on many other probes of planets and comets, including moon and mars, being used alone, in arrays or as feeds for parabolic reflectors, its circular polarization and high gain and simplicity making it effective for space application.


72) Define Sky wave?

Waves that arrive at the receiver after reflection in the ionosphere is called sky wave.


73) Define Tropospheric wave?

Waves that arrive at the receiver after reflection from the troposphere region is called Tropospheric wave (i.e. 10 Km from Earth surface).


74) Define Ground wave?

Waves propagated over other paths near the earth surface is called ground wave propagation.


75) What are the type of Ground wave?

Ground wave classified into two types.

  • Space wave.
  • Surface wave.



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