GPM project has a future plan of rainfall measurement with the core satellite loading dual frequency precipitation radars, accompanied by about eight companion satellites that also mount the microwave radiometers. Microwave radiometer data are expected to be the central data for producing the global maps of rainfall rates for the reason that they are used for the observation from satellite more frequently and have the wider observation swath width. In order to improve the rain retrieval algorithm for space-borne microwave radiometers, it is imperative to improve the microphysics model and the rain distribution models that are used in the retrieval algorithms. One of the important observations was simultaneous measurements of precipitation with COBRA, 400MHz WPR and ground-based measurements of rain drop size distribution. Therefore, we analyze the vertical characteristics of rainfall related to rainfall type observed by the COBRA and the 2D-Video-Distrometer. As a result, in convective rainfall, vertical variations of the polarimetric parameter (ZDR and Do) were very large. Height dependency of the vertical profile of radar reflectivity was become clear.
