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. 24, 2015
Filed:
Feb. 16, 2011
Shigeru Matsuo, Hitachinaka, JP;
Katsuaki Tanaka, Hitachinaka, JP;
Shigeru Matsuo, Hitachinaka, JP;
Katsuaki Tanaka, Hitachinaka, JP;
Clarion Co., Ltd., Saitama-shi, JP;
Abstract
A navigation device that includes a map data base in which map information is stored and a positioning unit that determines a current position based upon a radio wave signal received from a satellite, contains: a tunnel detection unit that detects a tunnel that is present ahead on a road where the navigation device is moving; a travel data acquisition unit that acquires travel data of another vehicle from an information center; and a position estimation unit that in case the tunnel detection unit detects a presence of a tunnel ahead on a road and the travel data acquisition unit acquires from the information center travel data of another vehicle that has traveled through the detected tunnel, estimates a current position of the navigation device in the detected tunnel using a travel speed in the detected tunnel in the acquired travel data as a movement speed of the navigation device.