évanouissement par interférence

CONT: Interference fading: As [the] name indicates, it is the fading produced because of upper and lower rays of the sky wave interfering with each other. This is the most serious fading. It is also produced due to the interference between a ground wave and a sky wave or between sky waves reaching [a] receiver by different paths or different number of hops. For a single sky wave frequency, interference fading takes place due to the fluctuations in the height of the ionospheric layer or due to the variation in the ionic density of the layer.