ABSTRACT
The observation geometry is crucial in the Moon-Based SAR (MBSAR), as it defines the positions and orientations between the ground target and MBSAR and their relationship to the beam pointing direction. The MBSAR observation geometric model differs significantly from spaceborne SAR due to the Moon’s topography, irregular rotational motion, and highly perturbed orbit. This chapter investigates these components and their relation to the observation geometric model. We focus on the spatial and temporal reference frameworks and their reciprocal transformation. Building upon this basis, we thoroughly examine the relative motion between the Earth and the Moon under various scenarios. Upon attaining a thorough comprehension of the Moon orbiting Earth, we shall build the observation geometric model of MBSAR by considering the lunar orbital model, lunar topography, Earth ellipsoid, and their relevancies to beam pointing. By examining these factors in detail, we aim to provide a comprehensive understanding of MBSAR’s geometric model for Earth observation.
