Study On GPS Navigation System Based On GSM Network

GPS technology is widely used for global precise timing, ranging, navigating, and positioning system because of many of its advantages, such as high-precision, high-speed and low-cost, etc. With the development of communication technology, the service price of GSM network's SMS and GPRS are comparatively low, thus it is possible to send GPS positioning information via GSM network.In this paper, the principle of GPS positioning was introduced firstly, then, after analyzing the factors which impact positioning precision, a simulation for filtering GPS positioning data with kalman filter was done. The simulation results showed that kalman filter really does improve the positioning precision to some extent, besides, it can also reduce the divergence of error. Then short message service based on GSM is studied in detail include architecture, protocol, channel and the process of its sending and receiving. Based on this, we build a mathematic model to analyze the time delay and loss probability of short message transmitting, and get the corresponding simulation results, so it can direct the design of navigation system. On the following combining with one of the main jobs of this paper and the current research state of our lab, design of the circuit with AT91RM9200 as its CPU and the programming under ADS environment and Linux OS were also done at the end.