Abstract: The ground-surface reference frame is important in space perception. The sequential surface integration process (SSIP) hypothesis firstly speculated on its formation process. The SSIP hypothesis greatly promotes the development of research in space perception and opens up a new research field. The core viewpoints and relevant evidences of SSIP hypothesis include three aspects: the representation principle of the ground, the integration conditions, and the representation results. . Future research needs to investigate the formation mechanism of the ground reference framework by employing the process-based technology and the role of high-level cognitive process. The applications of the ground-surface reference frame in national defense should also be considered.

Key words: the ground-surface reference frame, ground representation, SSIP hypothesis, space perception