A passive mobile location system for UMTS

The purpose of this research is to assess the performance of a passive location system for UMTS. The system proposed will be located in the mobile receiver and will use TDOA measurements from surrounding base stations to estimate the mobile location. The system will not require to transmit thus will not adversely affect system capacity. Security implications are avoided as the mobile location will not be available to the network or other users. Due to the wide bandwidth proposed by the UMTS standard the potential time resolution of the TDOA estimates is high, higher than possible for current mobile standards. However the audibility of non-serving BSs is expected to be a problem. The location estimate accuracy can be improved further by filtering techniques (e.g. velocity prediction). Furthermore much of the required signal processing is already performed during the proposed mobile synchronisation procedure. Minimal configuration would be required by the network providers.