Mobile location estimation and tracking for GSM systems

This paper proposes a mobile location estimation and tracking technique for wireless communication systems. The location estimation is based on the differences of downlink signal attenuations, which are used to determine circles composed by possible mobile locations. Then the actual location is given by the intersection of the circles. The great advantages of this method are the non-necessity of a known and accurate path loss modelling and the reduction of shadowing effect. Furthermore, a mobile tracking technique via piecewise linear optimization using a simple genetic algorithm is applied to improve the locations estimation. As the results are shown, the estimation errors are much smaller than the errors from cell-ID method in a real GSM system.