Abstract:
It is well known that the ionosphere is not a uniform and homogeneous
medium. For many years studies have been made of ionospheric irregularities
down to sizes of less than 1 km; some of which are associated with periodic
motion caused by gravity waves, others, with turbulence phenomena. The
effect of these ionospheric disturbances on conventional high-frequency radio
communication links is an important study, and extends back to almost the
beginning of ionospheric investigations. It is now recognised, in fact, that
the Ionosphere behaves as an irregular reflector which imposes fluctuations
on initially plane wavefronts as they, emerge from the medium.