Comparative Study on Rainfall Rate Digital Map in China Land Area

Rain attenuation is the main impairment for radio communication systems operating at frequencies above 10GHz, and the rainfall rate data exceeded for 0.01% of the average year are the essential data for rain attenuation prediction. Three kinds of digital maps of rain rate (mm/h) exceeded for 0.01% of the average year in China land area have been compared and analyzed herein, which are the methods in Recommendation ITU-R P.837-7, P.837-4, and the grid data produced by using the statistical data in widely distributed station in China land area. The comparison shows that the method in P.837-7 is better than previous ITU-R method, but there are still many differences between the method in P.837-7 and the grid map obtained by the local data sources in China land area.