Research And Implementation Of GPS Positioning Algorithm In ARM System

Global Positioning System (GPS) has become more and more widely applied in all aspects of real life, the research of GPS terminal system has been one of the hotspots in the field of orientation and navigation in domestic. GPS technique has been applied in China nearly two decades. But until now, the key techniques of high-precision GPS receiver are from abroad. Developing autonomously low-cost and high-precision GPS receiver is important for our country. With the development of embedded technology, Getting receiver position using the satellite-raw data and implementing filtering algorithm in embedded systems are important part of developing low-cost and high precision of the receiver.In this paper, Around research and implementation of GPS positioning algorithm in ARM System, the following work were completed for the goal of developing low-cost and high-precision GPS positioning products:First, in order to achieve the goal of calculating the receiver's position, the satellite transient coordinates was computed using ephemeris data which was extracted from the raw data outputted by Rockwell's JUPITER GPS-OEM board according to the navigation message format. Combined the calculated coordinates of satellite with the pseudorange extracted from the OEM board information, the receiver position was caculated basing GPS positioning principle successfully, and the experimental results of the receiver position solution was gave.Second, in order to improve GPS positioning accuracy, a GPS dynamic filter mode was established. Based on this model, the receiver position computed using navigation message was filtered using the extended Kalman filter algorithm. Experimental results show that the filtering algorithm improves the positioning accuracy of GPS receiver.Finally, in order to achieve GPS positioning algorithm in embedded system, the system's hardware architecture using the ARM processor core and related software was designed. the software of GPS data acquisition and graphics interface were implemented respectively using C + + language and QT. The experimental results show that the system realizes the GPS data acquisition and display.