Evaluation of a time-delay based geolocation algorithm in real UMTS networks

Time-delay geolocation based on information reported in measurements reports (MRs) is possible for mobile stations (MSs) making active calls in a live UMTS network. This paves the way for important applications like traffic map generation or accurate radio propagation modeling. Nevertheless, there is a number of constraints that will impact the accuracy of geolocation of MSs such as multipath, limited number of measured base transceiver stations (BTSs), non-perfect BTS synchronization recovery, measurements errors, and MRs not being sent in a continuous way but in an event-driven fashion. This paper quantifies the effect of the aforementioned limitations in real networks with the help of drive-test measurements, proposes several techniques to mitigate them, and finally analyzes in detail the impact on the geolocation accuracy.