Réda Dehak

Spatial reasoning with relative incomplete information on relative positioning

By Réda Dehak, Isabelle Bloch, Henri Maı̂tre

2005-09-01

In IEEE Transactions on Pattern Analysis and Machine Intelligence

Abstract

This paper describes a probabilistic method of inferring the position of a point with respect to a reference point knowing their relative spatial position to a third point. We address this problem in the case of incomplete information where only the angular spatial relationships are known. The use of probabilistic representations allows us to model prior knowledge. We derive exact formulae expressing the conditional probability of the position given the two known angles, in typical cases: uniform or Gaussian random prior distributions within rectangular or circular regions. This result is illustrated with respect to two different simulations: The first is devoted to the localization of a mobile phone using only angular relationships, the second, to geopositioning within a city. This last example uses angular relationships and some additional knowledge about the position.

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A novel method to fight the non-line-of-sight error in AOA measurements for mobile location

By Emmanuel Grosicki, Karim Abed-Meraim, Réda Dehak

2004-06-01

In Proceedings of the IEEE international conference on communications (ICC)

Abstract

In this contribution, a mobile location method is provided using measurements from two different Base-Stations. Although computationally from two different Base-Stations. Although based on a simple trilateration and takes into account error measurements caused by Non-Line-Of-Sight (NLOS) and near-far effect. The new method attributes an index of confidence for each measure, in order to allow the mobile to select the two most reliable measures and not to use all measures, equally.

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