A model for attenuation by precipitation on a microwave earth-space link


  • Pierre Misme,

  • Philippe Waldteufel


A prior study shows that a precipitation model based on the concept of rain cells permits one to predict in a satisfactory way the attenuations occurring on a line-of-sight link at frequencies superior to a few gigahertz. The present work aims to extend this model for slanted paths. To begin with, various types of precipitation are identified. Then the effect of altitude on attenuation coefficients is looked into, allowance being made for changes in air density and temperature. Finally, the geometry of the model is adapted to slanted paths. Test comparisons reveal a fair agreement between observations and model predictions. A computing program permitting rapid calculations to be made is provided in an appendix.