The space-variant motion errors are specific to different targets and proportional to the beamwidth of a synthetic aperture radar (SAR) system, which makes them very difficult to be compensated for a SAR system with wide beamwidth. In this paper, a motion compensation (MoCo) algorithm that exploits the features of the geometry of near-range SAR applications is proposed. By dividing the whole range swath into several octave sub-swaths, the effects of space-variant motion errors can be greatly reduced, especially for targets at nearer range, with low computational load.