Database Correlation Method for Multi-System Positioning

The objective of this paper is to propose and evaluate database correlation method (DCM) for user positioning in heterogeneous network environment. The work is based on DCM developed earlier at VTT Research Centre of Finland. The proposed algorithm is capable of exploiting and combining measurements originating from multiple different networks (e.g. GSM and UMTS) and it utilizes filtering techniques (Kalman filtering) as well as external data (vectorized street network for map-matching) to further improve the positioning accuracy. Field trials are carried out to collect terminal measurement data from real operational GSM and UMTS networks, and from a WLAN indoor network. These measurements are used to evaluate the implemented algorithms. The results show that the proposed multi-system positioning algorithm with post-processing techniques improves positioning accuracy compared to the DCM resorting to only one network or without post-processing techniques