The Research And Application Of Location Algorithm In The Precise Location Service Platform

With the wide spread of location-based services, the demand for precise location services has greatly indreased. The precise Location Service Platform emerged to meet this demand. The platform described in this thesis is a location platform which is implemented based on the SUPL(Secure User Plane Location) specification released by OMA (Open Mobile Alliance), the RRLP (Radio Resource LCS Protocol) published by 3GPP(3rd Generation Parnership Project) and the A-GPS (Assisted-Global Position System) specification regulated by China Mobile. It adopts the stand alone positioning algorithm to compute the assisting data and user's position.Combing the author' s theory research and practice, this thesis address main work done by the author. The main work include two parts: the first part presents the system architecture of the precise location service platform and implement it; the second part presents the research on the stand alone positioning algorithm in the precise location service platform.Firstly, this thesis briefly introduces the marketing background, the main positioning technologies and the related international location specifications of precise location service platform. Also, the overview of the precise location platform is included in chapter one.In chapter two, the implementation of the precise location platform is explained in details, with main focus on the general architecture of the platform and the implementation of the module of SUPL location platform (SLP). This chapter describes the main interfaces with other external entities, the main functional entities of SLP and the key data structures.In chapter three, the thesis focuses on the research of the positioning algorithm and its implementation in the platform, including the conversion of the GPS navigation messages to engineering units, the stand alone position calculation, the calculation and encapsulation of assisting data, and the calculation of the terminal's position.The last chapter gives a prospect of the location platform based on the current market situation. Meantime, the thesis proposes some advices on the improvement of the positioning algorithm.