Motion Compensation of Interferometric Synthetic Aperture Radar

Synthetic aperture radar (SAR) is a digital signal processing technique which enhances the azimuth resolution of a radar image using the target Doppler history created by the motion of the radar platform. If the platform deviates from a constant velocity, straight-line path then image quality is lost and image details become unfocused. Motion compensation (MOCO) is a technique in which the position and attitude of the platform is recorded or estimated and then used to correct the scene’s Doppler history as if a straight-line, constant velocity path had been taken. Brigham Young University’s interferometric synthetic aperture radar (YINSAR) was flown on a Cessna Skymaster which experienced significant motion due to the aircraft’s small frame. But using multiple motion sensors, such as an inertial measurement device and various GPS units, the motion can be compensated for. This report discusses some basic SAR theory, discusses SAR interferometry, gives a brief description of YINSAR and measurement devices, investigates various SAR motion compensation algorithms, and displays selected image results from YINSAR