Studies on acquisition and tracking threshold's reduction for GPS spaceborne and aeronautical receivers

René Landry (1) , Laurent Lestarquit (1) , Jean-Luc Issler (1) , Abdelahad Benhallam (2)

1 CNES - Centre National d'Études Spatiales [Toulouse]
2 ENAC - Ecole Nationale de l'Aviation Civile

This paper describes a method for threshold?s reduction taking into account features both concerning GPS receiver modification and gain on the performances improvement. This method involves two steps. The goal is to use the strong channels of the GPS receiver which are actually tracking satellites for velocity aiding the other channel trying to acquire or track satellites presenting a low signal over noise ratio due to lower elevation or masking conditions. Second, according to the theory and the characteristics of the digital internal loops of the GPS receiver, the predetection bandwidth is reduced to the lowest value permitted by the velocity aiding accuracy. This technique allows to improve the GPS accuracy and robustness. The paper proposes and identifies the automatic model of a velocity aided loop. Furthermore, to allow the validation of the described threshold reduction method, the technique is proposed to be inserted and validated into a software simulator of a GPS receiver model. The on-going work is intended to be applied for space and aeronautical applications.

Domaines: Informatique [cs]; Traitement du signal et de l'image [eess.SP]; Sciences de l'ingénieur [physics]; Traitement du signal et de l'image [eess.SP]

René Landry, Laurent Lestarquit, Jean-Luc Issler, Abdelahad Benhallam. Studies on acquisition and tracking threshold's reduction for GPS spaceborne and aeronautical receivers. ION GPS 98, 11th International Technical Meeting of the Satellite Division of The Institute of Navigation, Sep 1998, Nashville, United States. pp 619 - 625. ⟨hal-01021675⟩