Research, Positioning Technology Based On The Gsm System

It has been researched for many years in the area of using mobile platform directly in location. In recent years, the increasing requirements for the location of mobile platform users further promoted this work. The law of E-911 enacted from FCC in 1996 demanding that, from October 1, 2001, cell network should be able to provide the locating services with the precision within 125m and the accuracy of 67 percent for the mobile platforms which send out emergent calls. In 1998, the regulation of the service was modified to the precision of 400m and the accuracy not lower than 90 percent. In 1999, FCC again demanded that the location services based on network should have the precision of 100m with the accuracy of 67 percent, or the precision of 300m with the accuracy of 95 percent, and the services based on mobile platforms should have the precision of 50m with the accuracy of 67 percent, or the precision of 150m with the accuracy of 95 percent. The regulations of FCC greatly improved the development of the cell wireless location technology. Implementing the location of the mobile platforms in the cell system not only satisfying the requirements of E-911, but being very important in the following ways:(1) flexible billing system based on the location of mobile platforms, which means different billing standards could be used according to different locations of the mobile platforms.(2) Intellectual transformation system(ITS), ITS is able to provide the locations of the vehicles and travelers, and other services like vehicles scheduling, tracking, and so on.(3) Network optimizing and resource management, mobile platform precisely monitoring. This can help deciding the best time for section switching. At the same time, dynamically allocating the channels according to their location also helps enhancing the utilization of spectrum and making good use of network resources. (4) Information services. Locating the mobile platforms and travelers and providing them with the information and other services offered by the area they belong to.Since the enaction of the law of E-911, based on the compulsive regulations and the driving of market benefits, people have taken more and more attention to the research of location, especially the wireless location. Many universities and institutes have begun their research in the field.Based on the intensive research of the location technology of wireless cell telecommunication system, this thesis describes the basic theories, location methods and application characters of how to implementing this technology. Moreover, through the discussions of path wear out model of the wireless channel and the results of the field testing examinations, it put forward a method which can be used in implementing the location according to the power intensity of the receiving signals, and also develops a demonstration system of location based on the GSM telecommunication network. Furthermore, according to the working results of the demonstration system, the thesis also designs the scheme of the implementation of locating services, utilizing the resources offered by the GSM telecommunication networks. At last, aiming at the errors existed in the implementation of location in the process of moving, this thesis discusses a tracing and locating method for the mobile platforms.