Method to Reduce Imaging Errors in Dynamic Target Observation of the Geostationary Interferometric Microwave Sounder

The Geostationary Interferometric Microwave Sounder (GIMS) is a synthetic aperture microwave sounder working in time-sharing sampling mode with a rotating circular antenna array, thus having a relatively long imaging period. Since target motion in the imaging period will pose a problem to imaging effect, observing dynamic target such as fast changing weather of tropical cyclones will introduce imaging error to the retrieved image of GIMS. A method that combines Kalman filter and interpolation to reduce imaging error are presented, which utilizes a time sequence of visibilities collected by time-sharing sampling method. Simulations of GIMS's observation process in viewing a series of near real case brightness temperature maps modeled by the National Center for Environmental Prediction Final Operational Global Analysis data/Weather Research and Forecasting Model/Radiative Transfer for Television Infrared Observation Satellite Operational Vertical Sounder method, together with postprocessing of dynamic observation error-correction processing and image retrieval are conducted for the method. Results show that the method can reduce imaging error even if there are random noises in visibilities.