The Research Of Digital Surveying And Mapping In Network Based On GPS And PDA

With the fast development of the computer and Survey technology,the Mobile GIS data collection system based on embedded computer, wireless network and GPS positioning technology has been matured. Compared to the traditional GIS field data collection methods, Mobile GIS data collection system is not only easy to carry but also reduce the human and material resources, the more important thing is that the data collected is "measured is significant", which greatly improved the work efficiency. This paper based on the idea that GIS data acquisition means based on GPS and GIS technology, make use of the GIS data collection methods and network geographic information system technology ,with the Object-oriented thinking of geographic information, designed a Digital network Mapping System Framework based on GPS and PDA,and realized initial prototype of the system.The current Mobile geographic information data acquisition system is based on stand-alone mode, which generally has no interaction with the server, the data also need to transfer to the geographic information database after the GIS data acquisition, so it can not collect and process the data at the same time by many people. Given the deficiencies of the current system,this thesis uses the ArcGIS Server Mobile SDK to design the mobile digital mapping system in hardware platform based on GPS and Pocket PC, one type of PDA with the Windows Mobile 5.0 operating system, and sends the collected data to the spatial database SDE Geodatabase real-time in server-side,making full use of the wireless communication functions (such as GPRS) of PDA. The thesis first investigates the key technologies involved in the frame of the system, then designs the framework of the system.For the mapping, pipe network data acquisition and resources survey and other digital mapping operations, the paper has a certain value.The main results and innovation of this thesis are as following:1) The design achieved "measured is significant" in the mobile data collection terminal by many people at the same time, More importantly,and realized the capability of synchronizing data transfer between the mobile terminals and the server-side.2) This thesis use a new way of GIS data acquisition, which does not have fixed maps to increase data acquisition into the work area, but just downloads edge parts of data from the server, and then GIS data acquisition can be started near the edge part of data .