Abstract: A bistatic synthetic aperture radar (SAR) imaging system and method include: combining each radar return pulse from airborne radar platforms with a sinusoid; deskewing each reduced radar return pulse; estimating motion parameters based on a maximum likelihood estimation (MLE); performing MLE motion correction to generate motion-corrected radar return pulses; acquiring position and velocity estimates of the airborne radar platforms and scattering locations; defining bistatic range and velocity vectors; defining new bistatic range and velocity vectors in a new set of orthogonal axes; projecting vector distance differences between the radar scattering locations along the new set of orthogonal axes to generate new range and velocity measurements along the new set of orthogonal axes; converting the new range and velocity measurements to map Doppler frequency into cross-range; and forming a bistatic SAR image in range and cross-range based on cross-range extent derived from the Doppler frequency mapping.

Abstract: A synthetic aperture radar imaging method that combines each radar return pulse with a sinusoid to reduce the radar return pulses to a baseband frequency and deskew each radar return pulse. It includes determining a maximum likelihood estimate (MLE) of residual motion parameters for a dominant scatterer on the ground relative to the airborne radar and correcting for errors in inertial navigation system measurements based on the MLE residual motion parameters. It includes convolving each radar return pulse with its corresponding radar transmission pulse to generate a range compressed image for each radar return pulse and generating a sub-band range profile image for each radar return pulse and its corresponding radar transmission pulse based on the corresponding range compressed image that has been corrected for residual motion. Performing bandwidth extrapolation on each sub-band and subsequently combining the three bands to produce an enhanced resolution image without grating lobes.

Abstract: Embodiments of synthetic aperture radar systems for mapping Doppler frequency to cross-range to form bistatic inverse synthetic radar images of airborne targets.

Abstract: System and method for calculating three dimensional residual motion errors of a moving platform with respect to a point of interest by receiving a radar signal from the point of interest (302); forming a radar image including a plurality of scatterers (304); using an MLE method to obtain range, radial velocity and acceleration of the moving platform for a first peak scatterer in the radar image (306); correcting a location of the first peak scatterer with respect to a scene center of the point of interest (312); updating the obtained radial acceleration responsive to the corrected location (314); and updating the obtained radial velocity of the moving platform responsive to the updated radial acceleration (316).

Abstract: System and method for calculating three dimensional residual motion errors of a moving platform with respect to a point of interest by receiving a radar signal from the point of interest (302); forming a radar image including a plurality of scatterers (304); using an MLE method to obtain range, radial velocity and acceleration of the moving platform for a first peak scatterer in the radar image (306); correcting a location of the first peak scatterer with respect to a scene center of the point of interest (312); updating the obtained radial acceleration responsive to the corrected location (314); and updating the obtained radial velocity of the moving platform responsive to the updated radial acceleration (316).