Research,Design And Realize On The Embedded Electronic Map Based On Handheld PC

Embedded GIS is a kind of newly developing application field. It is a production of the combination of GIS and newly developing embedded hardware. It is the extension, supplement and development of intrinsic GIS field. The typical application of embedded GIS is made up of embedded hardware system, embedded operating system and embedded GIS software. Embedded GIS can be widely applied to traffic, military affairs, mapping, medical treatment, automobile navigate and so on, with the development of communication technology, computer technology, embedded technology, the application domain of embedded GIS will be wider.At the beginning of the thesis, it analyzes the research progress, technology background, characteristic and applications of Embedded GIS. Then it brings forward the complete logical framework design and function module design of Embedded GIS system based on Handheld PC. Further more, it puts emphasis on several key technologies on realizing Embedded GIS:(1) Transplanting the general-purpose electronic maps data in PCs to Handheld PCs to make use of existing resource adequately and reduce the difficulty of building electronic map;(2) Bring forwarding the data model of multi-scale digital map based on PDA platform;(3) Building the quadtree applying to the Embedded GIS to improve the search efficiency of the whole quadtree;(4) Optimizing the data access in the Embedded GIS to improve the speed of the electronic map display and searching;(5) Realizing the self-adaptive labeling to the following effect. For those elements visible in the current windows, the system can adjust the positions of their labels and show the labels in the current screen with a good visual expression;...