APPLICATION OF THE GPS SYSTEM TO A RAILWAY NAVIGATION SYSTEM USING TWO SATELLITES AND A MEMORIZED DATABASE

摘要

P A method of locating a vehicle whose movement is limited to a route whose location is fixed and known, such as a train is described. An initial estimate of the location is made based on the information contained in a route database, based on the distance traveled from a predefined point. The accuracy of the estimated vehicle location is enhanced by the use of only two global positioning satellites. / P