Precipitation radar onboard TRMM satellite

A precipitation radar (PR) onboard the TRMM satellite has been developed by NASDA. The PR employs a 128-element active phased array and can measure the 3-dimensional rain distribution over the swath width of 215 km with a resolution of 4.3 km in the horizontal and 250 m in range. Functional tests of the PR were performed and it was confirmed that performances of the PR satisfy TRMM mission specifications.