Results from the 19- and 28-GHz COMSTAR satellite propagation experiments at Crawford Hill

Strong interactions of radio waves with rain and ice particles in the lower atmosphere significantly affect the performance of earth-space radio links operating at frequencies above 10 GHz. Because of the uncertainties and variabilities in the microstructures of weather phenomena, direct measurements of the effects of rain and ice on radio propagation are needed for the economic design of reliable satellite communications systems. Unique and comprehensive space-earth propagation measurements have been made at Crawford Hill, New Jersey, using the 19- and 28-GHz beacons on the COMSTAR satellites. This paper summarizes these measurements of rain attenuation, rain and ice depolarization, phase and amplitude dispersion, off-path rain-scatter coupling, angle-of-arrival variations, and cloud scintillation. These results provide empirical design data and will serve as checks on theoretical models needed for predicting communication system performance in geographical regions where measurements are not available.