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针对海量、高速运动的空间目标检索查询效率低的问题,提出一种基于轨道约束的空间目标球面网格索引构建方法。该方法利用地球惯性系下空间目标轨道相对稳定的特性,通过维护球面剖分网格内途经的空间目标列表,实现了对高速运动目标的稳定索引。在此基础上,提出基于目标球面网格索引的区域查询应用方案,首先,依据一定步长离散查询时段;然后,计算查询区域在惯性空间的边界点坐标并确定交叉网格;其次,提取网格中的空间目标,计算并判断目标与区域的位置关系;最后,递归查询整个时段,实现空间目标过境查询分析。仿真实验中,传统逐目标查询方法耗时与目标数量线性正相关而与区域大小无关,单目标平均耗时0.09 ms;与之相比,所提方法用时随区域面积减小呈线性递减,区域格网数小于2 750时,时间效率高于对比方法,且能够维持相当的准确率。实验结果表明,该方法在实际区域应用中可以有效提升查询的效率。
Aiming at the problem of low search efficiency of large-scale and high-speed spatial target retrieval, this paper proposes a method to construct spatial target index based on orbital constraint. The method takes advantage of the relative stability of the space target orbit under the inertial system of the Earth and realizes the stable index of high-speed moving objects by maintaining the space target list in the spherical meshing grid. Based on this, a scheme of regional query based on the index of the target spherical grid is proposed. First, the query period is discretized according to a certain step. Then, the coordinates of the boundary of the query region in inertial space are calculated and the cross-grid is determined. Secondly, The spatial target in the grid, calculate and determine the location of the target and the region; Finally, the recursive query of the entire period, to achieve spatial target transit query analysis. In the simulation experiment, the traditional method of target-by-target query time-consuming is linearly and objectively related to the number of targets but has no relation with the size of the target. The average time spent on a single target is 0.09 ms. Compared with the method, the proposed method decreases linearly with the area decreasing, When the number of grids is less than 2 750, the time efficiency is higher than that of the comparative method, and a considerable accuracy can be maintained. The experimental results show that the proposed method can effectively improve the query efficiency in the practical application.