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:
Feb. 08, 2011
Filed:
Apr. 19, 2010
Shinichi Mitsunaga, Kanagawa, JP;
Shinichi Mitsunaga, Kanagawa, JP;
Seiko Epson Corporation, Tokyo, JP;
Abstract
A reception environment is determined to be a multipath environment when the difference (positioning altitude difference) between the maximum value (maximum altitude) and the minimum value (minimum altitude) of the altitudes of candidate present positions P of respective satellite sets exceeds a given threshold value (e.g., 200 m), and is determined to be an open-sky environment when the positioning altitude difference is equal to or less than the given threshold value. When the reception environment is the open-sky environment, an evaluation point E of each satellite set is calculated using a known evaluation method based on the number of satellites, a PDOP value, and the like. When the reception environment is the multipath environment, the evaluation point E of each satellite set is calculated in the same manner as in the open-sky environment, and a change amount ΔE corresponding to the difference (altitude difference) between the altitude corresponding to the preceding located position acquired from an altitude table and the altitude of the candidate present position of the target satellite set is subtracted from the evaluation point E.