%0 Journal Article %T A Simple Three-Dimensional Matrix Method for Global Constellation Intrasatellite Link Topological Design %A Xiaoliang Wang %A Yansong Meng %A Zhe Su %A Gang Wang %A Lixin Zhang %A Deren Gong %J International Journal of Navigation and Observation %D 2014 %I Hindawi Publishing Corporation %R 10.1155/2014/502158 %X A three-dimensional matrix method is proposed in this paper for Global Navigation Satellite System (GNSS) constellation Intrasatellite Link (ISL) topological design. The rows and columns of proposed matrix contain the information of both constellation orbit planes and satellites in each orbit plane. The third dimension of proposed matrix represents the time sequences during constellation movement. The proposed method has virtues of better advantage of conceptual clarity and computational efficiency, meanwhile, some properties of ISLs in the constellation can be proved easily. At the second part of this paper, a link assignment and optimal routing problem is proposed using three-dimensional topology matrixes, which aimed to minimize the relay hops during the process of data uploading to whole constellation network. Moreover, some practical constrains as antenna beam coverage and relative velocity are considered and analyzed in detail. Finally, some numerical simulations are provided, and the results demonstrated the promising performance of proposed topological method in reduction of computation burden, clear ISL conception, and so forth; the efficiency of provided optimal ISL routing problem is also proved. 1. Introduction With the rapid progress in GNSS technology, it is now feasible and necessary to build ISL network to increase system functions as communications and range measurements. One of the most important aspects in satellite constellation ISL analysis is the topological design. In previous researches, Werner [1¨C3] provided geometry of Virtual Path Connection (VPC) topological representation method for the analysis of the ISL between the satellites. In a series of literatures of Werner, ¡°LEONET,¡± a Medium Earth Orbit (MEO) satellite constellation has been taken as an example, which is on the basis of proposed topology method. Moreover, the actual needs for global data relay and transmission are considered. By using the idea of Asynchronous Transfer Mode (ATM), Werner also provided a Modified Dijkstra Shortest Path Algorithm (M-DSPA) to achieve the global transmission of data with end-to-end performance. Donner et al. [4] carried out in-depth study of routing algorithm according to the Werner¡¯s topology method, and Lee and Kang [5] also provided an application case of global Search and Rescue (SAR) using Werner¡¯s results. Chang et al. [6] proposed a graphical method for ISL topology design for a Low Earth Orbit (LEO) communication satellite constellation, and a two-step optimized search routing algorithm was given for global data relay and %U http://www.hindawi.com/journals/ijno/2014/502158/