Abstract: For the index of historical trajectories of moving objects, most of the schemes arc based on outdoor space,which are hard to be directly applied to indoor space. Moreover, the object itself is not indexed as an independent dimension and the efficiency of the queries based on objects is ctuite low. Thus, this paper proposed an index structure DR-tree(Dual R-tree) which can index three dimensions,such as the localization,the object and the time. I}his scheme can convert the three-dimension index into two two-dimension index by decoupling the location and object dimension,and provide query optimization method. I}he experimental results show that compared with RTR-tree, DR-tree, the scheme can not only support the efficient spatiotemporal query,but also provide the trajectory query based on objects.

Key words: Moving objects index, Indoor space,DR-tree,Object trajectory query