A Novel High-Resolution Asteroid Imaging Method Based on Joint Estimation of Motion and Topography

TY - JOUR

T1 - A Novel High-Resolution Asteroid Imaging Method Based on Joint Estimation of Motion and Topography

AU - Wei, Yi

AU - Ding, Zegang

AU - Li, Gen

AU - Zhang, Guangwei

AU - Sun, Yufei

AU - Yu, Xiaohan

N1 - Publisher Copyright: © 1980-2012 IEEE.

PY - 2026

Y1 - 2026

N2 - Earth-based radar plays a critical role in high-resolution asteroid imaging. However, traditional methods often suffer from range-azimuth defocusing due to the rapid translational and complex rotational motion of asteroids. Moreover, integration across subapertures is required to improve the signal-to-noise ratio (SNR), which in turn demands accurate surface topography information. To this end, this article proposes a novel high-resolution asteroid imaging method based on joint estimation of motion and topography. First, accurate translational parameters are estimated to mitigate the pulse-scale stretching effect (PSSE), thereby improving range focusing performance. A coarse-to-fine estimation for rotational parameters is then performed, starting with an initial estimate based on image-domain quality metrics, followed by aggregating information from multiple feature points to jointly estimate refined rotational parameters and local elevations. Finally, a coarse surface topography is reconstructed from the estimated elevations to support subaperture integration, resulting in a high-resolution image with enhanced SNR. The effectiveness of the proposed method is demonstrated through simulations and validated experimentally in a controlled microwave anechoic chamber.

AB - Earth-based radar plays a critical role in high-resolution asteroid imaging. However, traditional methods often suffer from range-azimuth defocusing due to the rapid translational and complex rotational motion of asteroids. Moreover, integration across subapertures is required to improve the signal-to-noise ratio (SNR), which in turn demands accurate surface topography information. To this end, this article proposes a novel high-resolution asteroid imaging method based on joint estimation of motion and topography. First, accurate translational parameters are estimated to mitigate the pulse-scale stretching effect (PSSE), thereby improving range focusing performance. A coarse-to-fine estimation for rotational parameters is then performed, starting with an initial estimate based on image-domain quality metrics, followed by aggregating information from multiple feature points to jointly estimate refined rotational parameters and local elevations. Finally, a coarse surface topography is reconstructed from the estimated elevations to support subaperture integration, resulting in a high-resolution image with enhanced SNR. The effectiveness of the proposed method is demonstrated through simulations and validated experimentally in a controlled microwave anechoic chamber.

KW - Asteroid imaging

KW - Earth-based radar

KW - pulse-scale stretching effect (PSSE)

KW - rotational parameters estimation

KW - translational motion compensation

UR - https://www.scopus.com/pages/publications/105027977090

U2 - 10.1109/TGRS.2026.3651507

DO - 10.1109/TGRS.2026.3651507

M3 - Article

AN - SCOPUS:105027977090

SN - 0196-2892

VL - 64

JO - IEEE Transactions on Geoscience and Remote Sensing

JF - IEEE Transactions on Geoscience and Remote Sensing

M1 - 5100614

ER -