Encoding and Operation for the Aperture-4 Hexagonal Discrete Global Grids on Uniform Tiles

  Objectives  Discrete global grid systems are the preferred data models supporting multisource geospatial information fusion. Hexagonal grids have become more popular in many applications due to their geometric characteristics within uniform adjacent.

  Methods  We design a uniform tiles hierarchy on the surface of the icosahedron according to the characteristics of the aperture-4 hexagonal discrete global grids, using complex numbers to build a unified coding and operation model. We also design algorithms including interoperating between geographic coordinates and codes, querying neighborhood codes.

  Results  The experimental results show that interoperation between geographic coordinates and codes efficiency of the proposed algorithm is approximately 2.74 and 1.73 times that of the traditional algorithm respectively, and that neighborhood codes query efficiency of the proposed algorithm is approximately 7.46 times that of the traditional algorithm. As the grid level rises, the advantages of the proposed algorithm become more obvious.

  Conclusions  The results of this paper are expected to provide theoretical and technical supports for the unified organization, management, processing and analysis of multi-source earth observation data.