Location Determination in OFDM-Based Mobile Radio Systems

In this thesis, location determination algorithms for cellular mobile radio systems employing orthogonal frequency division multiplexing (OFDM) are investigated. For location estimation, usually timing measurements between the base stations and the mobile station are performed, where suitable algorithms for OFDM and corresponding performance bounds are derived. The timing estimation process is faced with different effects, e.g., limited number of pilot symbols or inter-cell interference, that decrease the accuracy of timing estimates, and hence, location estimates. Therefore, a feedback of decided data symbols is proposed, where particularly data-aided timing estimation and interference cancelation are considered. Simulation results for a Long Term Evolution (LTE) system show the ability of these approaches to improve the accuracy and reliability of location estimates for static and dynamic mobile stations.