The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 14, 1998
Filed:
Dec. 16, 1996
Alain Renard, Chabeuil, FR;
Bernard Fouilland, Fauconnieres, FR;
Sextant Avionique, Velizy Villacoublay, FR;
Abstract
The disclosure pertains to receivers for positioning by satellite. To reduce the harmful effects of the paths reflected on the GPS measurement of position which should take account only of the path of the radiofrequency signals in direct line of sight, a method is proposed enabling the elimination of the influence of the multiple paths by simple extrapolation computation. Measurements are made by correlation with four pseudo-random codes E1, E2, L1, L2 that are replicas of a code received from a satellite. A first set of measurements of correlation energy values and of time received is carried out with the codes E1, L1 corresponding to an advance and a delay d with respect to a punctual code and a second set of measurements is carried out the codes E2, L2 corresponding to an advance and a delay k.d (k being different from 1 and 0). By linear extrapolation, a deduction is made therefrom of the measurements for k=0, which no corresponds to the case where the multiple paths have no effect. The disclosed method and circuit can be implemented with only one servo-control loop or with two independent loops.