| Geographic information services have quietly stepped into our lives in recent years, and geographic information services are gradually being applied in various fielda now. With the development of GIS technology, wireless positioning technology of mobile terminals, wireless transmission technology of spatial information and mobile representation technology of spatial information services. It becomes true to learn and cognize the knowledge about surrounding and environment more clearly in the digital earth and the digital city. The capabilities of applying the information, especially the spatial information, are not only the privileges in the government, enterprises and scientists, but also the demands of the public. Being directed by the idea of serving the people, the new information-applying mode is proposed. Anyone can request to use the advantages which the science and technology bring us in anywhere. It should serve to the public and the society firstly. As part of these high-techs, the Mobile GIS Service was represented in this thesis.However, poor performance hardware of mobile terminals, narrow bandwidth of wireless networks and slow transmission of spatial data make enormous challenge for the application of mobile spatial information services. The emergence of mobile internet with its personalized mobile communicationa and massive internet inforamtion has changed people's life and working. Mobile computing will become mainstream computing environment, and mobile GIS becomes to the important growth point in GIS domain. This paper intends to put forward some new thoughts and methods on key technologies for mobile spatial information services and to validate them efficiency and practicability through theory and practice. Main researches and concrete work include following aspects:1. the composition and characteristics of mobile spatial information services are discussed and related key technologies of mobile spatial information services from the technical aspect are analyzed, including deployment and management technologies of spatial information, wireless positioning technology of mobile terminals, wireless transmission technology of spatial information and mobile representation technology of spatial information. The analysis about these technologies is the basis of the researches of mobile spatial information services.2. Discusses the technical issues involved in the combination of mobile GIS and grid GIS. Based on the analysis of geographic information services, mobile GIS, grid GIS, and other related technical, the technical issues that involved in the combination of mobile GIS and grid GIS includes:the spatial information services that fully consider the characteristics of mobile devices and fit for the mobile users need to be established; a reasonable mechanism for scheduling grid resources and information fault-tolerant strategy should be researched; the spatial data compression and the wireless network asynchronous data transmission must be supported; the spatial data access mechanisms for the balance of remote data access and local data storage need to be considered; the humanistic man-machine interface should be designed.3. Based on the analysis of the mobile environment characteristics, a mobile user oriented spatial information grid service model is designed, and the specific methods are presented. It is divided into spatial information service layer, grid management layer, wireless transmission layer and mobile terminal layer. The spatial information service layer is consisted by the numbers of mobile spatial information services in the network; the grid management layer supplies a geographic portal to deal with the mobile users' requests and manage the mobile services; the wireless transmission layer is the bridge between mobile user and grid service center; the mobile terminal layer, which access the grid by a lightweight embedded GIS program, is the client of the model.4. Integrated by Mobile Communication, Geographic Information System and localization technology, Location-based Services can have an effect on Emergency Aid, Logistics Management, Tourism and Entertainment; it's a promising add-on service. Specifically, restricted to its own conditions, mobile devices experience small memory, low capacity, narrow bandwidth and frequent disconnection issues.5. The dissertation includes the research and analysis of those relative questions of mainstream platform, exploration the technology, service discovery and registration of platform of geographic information services based on OpenGIS and Web Service.The main innovation of this paper can be concluded as follows:1. Explores the management mechanism of mobile spatial information service resources in grid environment. To decrease the bandwidth consumption, reduce the network latency, and fully considering the network instability, the way that build grid system for managing mobile spatial information services is discussed, and the grid management mechanism is designed and realized.2. Using the independently developed spatial database engine, the complete process for constructing a mobile spatial information service is introduced detailed. Then, through the grid directory and agent technology, the distributed heterogeneous mobile spatial information services are managed unified according to certain rules, so the requirement of parallel and implicit service communication in the grid environment is met.3. Paper discussed the data integration technologies faced multi information sources, the rapid searching and intelligent distilling technologies of layered magnanimity spatial data, two buildings' best route choice arithmetic based on the road network, interoperation in different GIS platform, GIS WAP Service faced the mobile communication mechanisms upward 2.5G, the system architecture based on Agent and MAS etc. All of above were separated from three directions, spatial information dealing, service and the demonstration system integration. These technologies were born from the engineering practice and experience.4. Studies on the spatial information service calling method for mobile devices in grid environment. The mobile devices use a lightweight embedded GIS program to access grid. First of all, the mobile device captures the GPS signals from GPS receiver, parses and processes the signal to position information; then, the GIS program organizes the XML request and sends to the grid service center; the center transfers the compressed spatial data which obtained by service calling back to the device asynchronously through a wireless network; the GIS program builds cache and cache index on the receive data, and uses the cache elimination mechanism to manage it finally, the program displays the result on the device screen.5. Combination of mobile GIS and grid GIS. Based on the analysis of geographic information services, mobile GIS, grid GIS, and other related technical, the technical issues that involved in the combination of mobile GIS and Ophone platform includes:the spatial information services that fully consider the characteristics of mobile devices and fit for the mobile users need to be established.
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