Estimating range and time varying Doppler centroids with Kalman filters

Doppler centroid estimation for synthetic aperture radar is range and time varying problem which cannot be completely solved by the classical Doppler estimation techniques. Problems arise because of the Doppler centroid slant range dependence. Also high attitude drift rates of the SAR carrier yield unpredictable Doppler centroid histories which vary drastically with time. To overcome these problems the author presents an approach for the unambiguous time varying Doppler centroid estimation using Kalman filters in the range frequency-azimuth time domain rather than the range position and azimuth time domain