混合式全球网格划分方法及编码研究

根据基于多面体剖分的球面网格划分方案和基于地理坐标的等间隔网格划分方案的优缺点及地图投影的特点,提出了一种混合式全球网格划分方法。这种划分方法将全球分成了六个面片,每个面片的每一边都是90°,其中四个面片处于南北纬45°之间,以等距离圆柱投影为基础,采用矩形网格覆盖;两个面片处于高纬地区,以极地正方形变换为基础,采用不规则四边形网格覆盖。详细地阐述了网格的编码策略及存储方式,并给出了网格编码与地理坐标之间的相互转换方法。

Research on a mix global grid data structure and encoding

Based on the advantage and disadvantage of equal space global grid data structure and spherical discrete grid system and characteristic of map projection, we bring formard a mix global data structure. The data structure divides the global into six faces that are all 90°on a side. Four equatorial faces comprise 360°of longitude and 90°of latitude 45°S to 45°N, which are covered with rectangles. Two polar faces utilize a squared projection of round polar caps in which circular latitude parallels map to concentric equidistaqnt squares, which are covered with triangles. The mode of grid coding and data storage is expatiated and the method that converts the grid code to geographical coordinate is proposed.