The rapid fading of radio waves reflected from sporadic-E ionization

A digital ionosonde has been used at Halley (75°31′S, 26°59′W) to examine the fading on time scales of a few seconds of 4.5 MHz signals reflected from sporadic-E ionization. Fourier analysis of the phase and amplitude of the signals is used to show that the fading arises from the interference of returns from discrete echoes. The locations of these echoes are derived from phase measurements at pairs of antennae separated in North-South and East-West directions together with information on group ranges.

Details