The oblique propagation fading data of each propagation mode are recorded by a new type of oblique incident ionosonde

which can distinguish different electric wave propagation modes.In the data processing

the maximum likelihood estimate is used to figure out the parameters of the typical distribution in a least squares sense

the cumulative distribution function is calculated

and then the Kolmogorov-Smirnov hypothesis examining the fading properties of signal strength

is applied to compare the experiment data with a standard normal distribution.The fading characteristics of the one hop radio signals for 1 000 km path do not meet the Rayleigh distribution or the normal distribution in the time-domain;However

the fading characteristics in the frequency-domain meet the normal distribution.