The dynamics of rain-induced fades

The dynamics of rain-induced fades on radio links is studied by evaluating the rate at which the first Fresnel zone volume fills with rain. The amount of water in this volume determines the fade depth, and the rate at which it fills establishes the fade slope. A compact expression for fade slope on a terrestrial path is derived. This expression shows that once the rain rate is specified, fade slope is very sensitive to differences in rain velocity. Thus, there is no unique relationship between fade slope and rain rate.<
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