Research And Implemention Of The Personal Navigation System Based On Embedded LINUX System

By perpetual development of embedded operating system, mobile computer technique is applied abroad in handheld device. Mobile computer system represented by PDA being incresingly popularization makes it good market outlook of handheld device with GPS navigation function. This paper mainly introduces a scheme applying the GPS navigation system of intellectual property rights in handheld terminal, which adopts Linux as embeded operating system and Qt/Embeded from Trolltech Company as application program platform.The coordinate system conversion and the map projection are the key technique in GPS navigation system. This paper analyses the definition and the basic principle of geographical coordinate system conversion firstly. Then it researchs the relationship of world geodetic system with local geodetic systems and the transformations from world geodetic system to local geodetic system and figures out the corresponding conversion formula.This paper also researchs transfer algorithm from world geodetic system to right angle coordinate system utilizing gauss projection to reduce the shape of projection. Using these algorithms in Chinese navigation system, it achieves the transformation from world geodetic system 1984(WGS-84) to Beijing 54 or Xi'an 80 coordinate system. And this paper researchs projection ways of coordinate such as the Mercator projection, Lambert projection and linear projection to achieve the conversion of level rectangular coordinate by latitude coordinate and geography. By the data received through GPS receiver device and the state of satellites with geographical information, it shows how to process the coordinate information data effectively.According to the requirement of small equipment, low power dissipation, simple man-machine interface, stabilization and easy operation, this project chooses Intel Xscale series processor-PXA255 to design the systematic hardware platform. Using Arm Linux of open source as the embedded operating system and Qt/Embedded as GUI platform, it is easy to set up the development environment of the application software. The project has finished porting Arm Linux, the drivers of TIM B-E010-2 GPS module, implementation of GPSD data communication module, and has optimized the data communication interface between GPS navigation application and GPS receiver module. According to the coordinates system conversion research results and algorithm of map projection, the project uses C and C ++ language to carry on the procedure code under Object-Oriented Design technology and has implemented the functions of object orientation, navigation, tracks, maps download.This paper provides the experimental result of the target system and summarizes insufficient of the system design in this project and also gives some imaginations of working in the future at last.