适用于移动终端的全球离散格网快速生成方法

Algorithm of rapidly generating discrete global grids for mobile devices

针对全球离散格网依据剖分方法和投影方式的不同,在实现方式、剖分速度、格网均匀性等方面呈现出较大差异的问题,该文顾及移动终端用户对高精度位置应用日益增长的需求,以及顾及移动终端计算性能较低的特点,分析了球面格网生成方法、格网向椭球面投影方式和几何变形特点。通过分析椭球面格网与球面格网间变形差异,该文认为球面格网代替椭球面格网在一定程度上能够满足不同精度的格网剖分需求。通过建立用户精度指标与剖分层次对应关系,提高了格网剖分的计算效率,可应用于移动终端等计算性能较低的设备。

Discrete global grids have differences in the grid implementation algorithm,subdivision speed,and uniformity.Considering the growing demands for higher precision positioning application from mobile device users,as well as the low computing performance of mobile device,this paper discussed the generating algorithm of icosahedron based spherical grids.The grid was constructed on spherical,however the globe was an ellipsoid,thus the paper also explored the projection method from spherical to ellipsoid.Then,the distortion performance of both was compared,and the results showed that the spherical grid was an optional for ellipsoid grid.Finally,the corresponding relations between precision requirement and subdivision level was established,which contributed to improve the computing efficiency of mobile devices.