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:
Jun. 14, 2011
Filed:
Dec. 18, 2008
Yoshiyuki Muraguchi, Shiojiri, JP;
Yoshiyuki Muraguchi, Shiojiri, JP;
Seiko Epson Corporation, Tokyo, JP;
Abstract
A positioning method in a positioning device that calculates a location of the positioning device by executing Kalman filtering includes, acquiring a satellite signal from a positioning satellite; predicting a state vector including a velocity component of the positioning device, and error covariance of the state vector; correcting the velocity component using a difference between a measured value and a predicted value of the reception signal frequency from the positioning satellite; determining accuracy of the corrected velocity component based on the error covariance; setting a velocity condition based on the determined accuracy; judging a moving state of the positioning device by comparing the corrected velocity component and the velocity condition; and calculating the location by executing the Kalman filtering with a filter characteristic changed according to the judged moving state.