Comparison of Radar Derived Rain Attenuation with the COMSTAR Beacon at 28.56 GHz for Summer and Winter Periods

摘要

A description of new results is given pertaining to an experiment whose aims are to test and improve the accuracy of radar derived slant path rain attenuation methods. These estimated results are compared with measured rain fade levels of the COMSTAR beacon signal at 28.56 GHz at Wallops Island, Virginia. The new data base corresponds to five rain days flanking the winter of 1978-79 during which 715 minutes of simultaneous radar and disdrometer data were obtained. Agreement between estimated and measured individual rain fade events was found to be generally good. Agreement between corresponding conditional cumulative fade distributions was excellent. As a basis for comparison with measured drop size spectra cases, the Marshall-Palmer distribution was injected into the radar program and found to give similarly good results for this data base. This result is consistent with the application of the Marshall-Palmer distribution for stratiform type rains as is generally the rain type for winter periods. (Author)