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  • Research Article
  • Open Access

Positioning Based on Factor Graphs

EURASIP Journal on Advances in Signal Processing20072007:041348

  • Received: 16 November 2006
  • Accepted: 16 April 2007
  • Published:


This paper covers location determination in wireless cellular networks based on time difference of arrival (TDoA) measurements in a factor graphs framework. The resulting nonlinear estimation problem of the localization process for the mobile station cannot be solved analytically. The well-known iterative Gauss-Newton method as standard solution fails to converge for certain geometric constellations and bad initial values, and thus, it is not suitable for a general solution in cellular networks. Therefore, we propose a TDoA positioning algorithm based on factor graphs. Simulation results in terms of root-mean-square errors and cumulative density functions show that this approach achieves very accurate positioning estimates by moderate computational complexity.


  • Computational Complexity
  • Quantum Information
  • Estimation Problem
  • Mobile Station
  • Cellular Network


Authors’ Affiliations

German Aerospace Center (DLR), Institute of Communications and Navigation, Oberpfaffenhofen, Wessling, 82234, Germany


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