A Maximum Likelihood TOA Based Estimator For Localization in Heterogeneous Networks

Mohamed LAARAIEDH, Stephane AVRILLON, Bernard UGUEN

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DOI: 10.4236/ijcns.2010.31004                

Abstract

In this paper, we exploit the concept of data fusion in hybrid localization systems by combining different TOA (Time of Arrival) observables coming from different RATs (Radio Access Technology) and characterized by different precisions in order to enhance the positioning accuracy. A new Maximum Likelihood estimator is developed to fuse different measured ranges with different variances. In order to evaluate this estimator, Monte Carlo simulations are carried out in a generic environment and Cramer Rao Lower Bounds (CRLB) are investigated. This algorithm shows enhanced positioning accuracy at reasonable noise levels comparing to the typical Weighted Least Square estimator. The CRLB reveals that the choice of the number, and the configuration of Anchor nodes, and the type of RAT may enhance positioning accuracy.

Keywords

Localization, TOA, Ranging, Weighted least square, Maximum Likelihood, Hybrid Data Fusion, UWB, WLAN, Cramer Rao Lower Bound

Conflicts of Interest

The authors declare no conflicts of interest.

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