Statistical Analysis of the Amplitude of Radio Waves Reflected from the Ionosphere

Abstract

The influence of travelling ionospheric disturbance (TID) on the probability distributions of the amplitudes and the difference between the successive amplitudes of radio waves (v_τ) separated by equal time intervals (τ) has been investigated. It is shown that the varying contribution of the steady-to-random component in the received echo gives rise to different types of basic distributions in the different successive portions of the TID and the combination of such distributions yields different types of distributions including that of the M-type. The probability distribution of v_τ remains unaffected by the presence of specular component and is found to be Gaussian even in the case of M-shaped amplitude probability distribution. The probability distribution of v_τ and the auto-correlation function have been applied to determine the rms value of the random velocity of the irregularities, and the implications of the results are discussed. Finally, the effect of the speed of the TID on the speed of fading is also discussed.