| US 7,548,600 B2 | ||
| Apparatus and method for compensating the drift of a local clock used as sampling frequency | ||
| Jérôme Laine, Sautron (France); and Jean-Paul Menard, Pornic (France) | ||
| Assigned to Sercel, Carquefou (France) | ||
| Filed on Nov. 08, 2005, as Appl. No. 11/268,738. | ||
| Claims priority of application No. 05 08071 (FR), filed on Jul. 28, 2005. | ||
| Prior Publication US 2007/0025484 A1, Feb. 01, 2007 | ||
| Int. Cl. H04L 27/08 (2006.01) | ||
| U.S. Cl. 375—355 | 15 Claims |
| 1. Method of data acquisition comprising the steps of:
sampling acquisition data at an imperfect sampling frequency FE provided by a local clock (100), thus forming a series of sampled and dated data E[k] having a time provided by the local clock (100);
measuring the frequency error of the local clock (100) by determining the sampling dates according to a universal time UTC(t) and gauging the local clock (100) to a reference clock of a satellite-based positioning system (200); and
collecting the sampled and dated data E[k] and turning on the satellite-based positioning system (200) so as to perform the gauging of the local clock (100); turning off the satellite-based positioning system (200) once the gauging of the local clock (100) has been performed; keeping the satellite-based positioning system (200) in the off state for the duration of validity of the gauging of the local clock (100).
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