Cellular location in urban environment using ray tracing

The paper discusses the problem of location a mobile cellular terminal within an urban, multipath-rich environment, using available geographical information such as terrain and building maps. The method suggested in the paper is the use of ray tracing in order to characterize the propagation environment. The paper focuses on single antenna location, namely a trilateration - based algorithm and suggests using a two stage algorithm - coarse and fine location in order to avoid ambiguities and control the location geometry. The main purpose of the paper is to present the problems encountered in implementation including inaccuracies in the geographical and network databases, signal fading, measurement accuracy, location ambiguity and geometric depletion of precision (GDOP). The paper presents a preliminary analysis and simulation of the suggested algorithm.