The Stepped-Frequency Microwave Radiometer (SFMR) measures surface wind speed and rainfall from aircraft. Using a large database of surface wind-speed measurements from the SFMR and dropwindsondes, the SFMR wind speeds are shown to be too high at low wind speeds and in heavy rain. The measurements are corrected using other rainfall measurements. Though the wind-speed measurements are still a little bit too high at the lowest wind speeds and in heavy rain, the bias is reduced in all conditions.
The full paper can be accessed at http://journals.ametsoc.org/doi/abs/10.1175/JTECH-D-14-00028.1.