Database correlation method for UMTS location

The implementation and usage of many location-based services focuses in densely populated urban areas. In this paper we present a new approach, database correlation method (DCM), which takes advantage of the multipath characterized propagation in urban surroundings by utilizing the measured power delay profiles in the location estimation. The performance of the DCM is evaluated alongside with the 3GPP standard techniques, observed time difference of arrival (OTDOA) and cell identification (cell ID). Obtained results imply that DCM circumvents most of the urban environment related problems, contrary to the OTDOA, whose accuracy and availability are degraded. With DCM the achieved accuracy in simulations was 25 m in 67% of the estimates, which is adequate for most location applications and within the range required by emergency services.