Enhanced SAR Image Generation Using Ego-Motion Estimation Based on Ground-Scatterers for Automotive Radar Systems

In this paper, we present a novel radar system for estimating ego-motion from the ground-scattered signals and synthetic aperture radar (SAR) imaging based on the estimated ego-motion. Accurate ego-motion estimation is essential to obtain high-resolution SAR images, because the ego-motion determines spatial data sampling interval for SAR image generation. Our proposed method enables accurate ego-motion estimation by using the ground-scattered signals with a single-input single-output antenna system. We evaluate ego-motion estimation accuracy by comparing the generated SAR images of point targets. The SAR images generated using the proposed ego-motion estimation achieve an improved resolution of 0.284 m, compared to the 0.308 m resolution obtained with GNSS sensor-based ego-motion estimation. We confirm that the proposed method can generate enhanced SAR images using only radar sensors without requiring additional sensors.