Direct localization and detection of multiple sources in multi-path environments

In this contribution an algorithm for directly estimating the positions of multiple users of a mobile communication system in urban areas is presented. The approach is direct in the sense that the positions are estimated directly from the base-band signals received with an antenna array. The difficult problem of estimating the delays and directions of arrivals of all multi-path components is eliminated. Our new approach rather exploits the full space-time structure in the multi-channel model for the multi-path signals. The method overcomes the limitations of purely spatial array signal processing concerning the number of resolvable path and solves the extremely demanding data association problem inherent in conventional localization procedures. Furthermore, the approach is blind with respect to the knowledge of the transmitted signals. It solely exploits the knowledge of the pulse shaping filter and assumes that the locations of the main scatterers relative to the receiving antenna are known. Furthermore, results for the detection of the number of mobile stations in a multi-path environment are presented.