Simulation for spaceborne cloud profiling Doppler radar: EarthCARE/CPR

The Cloud Profiling Radar (CPR) on EarthCARE satellite is the first spaceborne cloud profiling Doppler radar using Wband frequency in order to measure vertical velocity of clouds and rain. The EarthCARE/CPR has -35dBZ in sensitivity after 10km integration and less than 1 m/s in Doppler velocity measurement error. Because satellite velocity and beam width spread Doppler spectrum and coherency is low, the measurement error of Doppler velocity is increased. EarthCARE/CPR is the first Doppler radar, so we need to make simulation data for the algorithm development, but the simulation itself is difficult in order to take into account these effects. The current method is calculated 2-dimentional integration within illuminated area by antenna beam and hit by hit for all pulses, then it takes many computation times. We developed the new simple calculation method, which is calculated using integrated antenna pattern, then the computation time is decreased significantly. This paper is reported the comparison for, both methods.