what is the meaning of VIRTUAL HEIGHT in terms of propagation of radio waves in ionosphere....plz.. include di

Answer 1

The time delay between the transmitted pulse and its echo provides an estimate of the effective height of the ionospheric reflection point. The virtual height is simply half the distance travelled during this time delay. Due to the retarding effect of the electrons on the radio wave as it passes through the ionosphere the virtual height (or more correctly, virtual range as the echoes do not necessarily come from directly overhead) are always an over-estimate of the true echoing range.

Answer 2

It relies upon on the form of wave you're speaking approximately. There are 2 varieties of waves in nature : one million) Mechanical Waves :- those waves, via definition, want a medium for their propagation. The medium must be elastic. Examples are sound waves, water waves etc. 2) Electromagnetic Waves:- those waves, via definition, don't desire a a medium for their propagation. It does no longer advise that they could't commute through a medium. occasion are easy waves, microwaves etc.

Answer 3

Not sure of the question but I think this might give u what u want. When calculating the Line of sight of over the horizon u use a earth radius of 4/3 earth.