Radar Path Attenuation Statistics Employing a Rain Field Visualization Methodology

Rain fade distributions are derived at a frequency of 15 GHz for the case in which paths intersect a "frozen simulated rain field" associated with a moving frontal system in the Mid-Atlantic coast. The paths, which transect the entire rain rate region, may be associated with either communications or radar systems. Path elevation angles from 2deg to 45deg are considered, where the results apply to the case in which a frontal system moves in the direction of the shorter dimension. A rain rate field was derived using a visualization methodology previously described by the author. Cumulative fade distributions are also calculated from simulations at other elevation angles, frequencies and rain rate zones. They are compared with measured results associated with earth-satellite beacon measurements executed by the author and other investigators. The simulated distributions are also compared with those predicted by models of the International Telecommunication Union-Radiocommunication (ITU-R). Close agreement is shown between simulated and measured results, whereas mixed agreement exists with ITU-R models. The simulation methodology has the advantage over other prediction models because results at low elevation angles may be achieved, and fade statistics may be conditioned to the presence of rain. Furthermore, the results may be specialized to moving rain regions of defined dimensions.