Analysis and migration of location-finding methods for

Abstract This paper initially reviews the current range of lo cation techniques on GSM networks, such as Cell-ID, GPS, A GPS, Time Difference of Arrival (TDOA) and E-OTD (En hanced Observed Time Difference). It shows how these tech niques can be applied to the future migration to 3G networks. The paper shows practical experiments of current accuracy of location and how these vary depending on the actual location of the mobile device. Along with this, the paper discusses new en hancements to TDOA (Time Difference of Arrival) and Cell-ID methods using improvements to the Timing Advanced signal. These are compared with practical experiments, along with typical accuracies. Index Terms- Locating-finding, GSM, 3G I