...Probability distribution function:累积概率分布函数（cumulative probability distribution function） F x probL ≤ x x概率密度函数probability density function : f x : F x ∫ ∞ f t dt在离散条件下，F（X）是阶梯函数。
The probability density function, cumulativedistribution function, average level crossing rate and average fade duration of each composite fading channel are analyzed, and some uniform expression.