Method and apparatus for estimating clock deviations, for virtual synchronization of free-running clocks and for determining the position of a movable object

US8363768B2 · kind B2 · utility

Assignees

• Fraunhofer-Gesellschaft zur förderung der angewandten Forschung e.V. · DE
• FRIEDRICH-ALEXANDER-UNIVERSITÄT ERLANGEN-NÜRNBERG · DE

Inventors

• Lucila Patino-Studencka · Nuremberg, DE
• Andreas Eidloth · Erlangen, DE
• Joern Thielecke · Erlangen, DE

Key dates

• Filing date: Mar 16, 2010
• Grant date: Jan 29, 2013
• Expiry date: Jan 17, 2031

Classification

• Technology area (CPC G): Physics
• CPC primary: G01S5/0226
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

In a method for estimating a deviation between a free-running transmitter clock and a reference clock, at a receiver stationary with respect to a transmitter, a transmitter signal generated by the transmitter on the basis of the transmitter clock is received. On the basis of the reference clock, a time of arrival of the transmitter signal and a beat phase of the transmitter signals carrier is determined. On the basis of a clock error model, the time of arrival and the beat phase, the deviation between the transmitter clock and the reference clock is estimated. The clock error model is derived by fitting a correlation function of a stochastic model to a measured auto correlation function of the transmitter clock. Deviations for a plurality of transmitters may be estimated and the transmitters may be virtually synchronized based on the estimations.