GPS device with compass and altimeter and method for displaying navigation information

• US 6,434,485 B1
• Filed: 09/14/2001
• Issued: 08/13/2002
• Est. Priority Date: 11/01/1999
• Status: Expired due to Term

• Current Assignee: Garmin Corporation (Garmin Limited)
• Original Assignee: Garmin Corporation (Garmin Limited)
• Inventors: Laverick, David J., Olivier, Tracy, Beason, Lawrence W., Burgett, Scott
• Primary Examiner(s): Beaulieu, Yonel
• Application Number:
  US09/952,601
• Time in Patent Office: 333 Days
• Field of Search: 701/213, 701/224, 701/207, 701/24, 342/120, 733/84
• US Class Current: 701/213
• CPC Class Codes: G01C 21/20 Instruments for performing navigational calculations G01C21/24, G01C21/26 take precedence
• CPC Class Codes: G01C 25/00 Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass testing, calibrating or compensating compasses G01C17/38
• CPC Class Codes: G01C 5/06 by using barometric means
• CPC Class Codes: G01S 19/45 by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement

Abstract

A portable, handheld electronic navigation device includes an altimeter, a compass, and a GPS unit. An internal memory stores cartographic data, for displaying the cartographic data on a display of the navigation device. Accordingly, the device is capable of displaying cartographic data surrounding a location of the unit as determined by GPS, heading information as determined by the compass, and altitude information as determined by the altimeter. Additionally, through operation of an input, a user can cause the display to move, and thus display additional cartographic information, in the direction of the compass heading even when the user of the device is standing still. Furthermore, through utilization of a clock, such as the GPS clock, a user can determine altitude changes over time. Also, the altimeter of the navigation may be calibrated with altitude information entered by a user, with altitude information obtained from the cartographic or with altitude information derived from GPS.

Claims

1. An altimeter comprising:

a processor;

a memory having topographical data, including altitude information, stored therein; and

a barometric pressure sensor for sensing atmospheric information from which said processor determines altitude information, wherein a correction factor for calibrating said altimeter is computed by said processor based upon supplemental altitude information input to said processor;

wherein said altimeter further comprises a GPS unit, wherein said GPS unit determines a location of said altimeter, and wherein said processor retrieves data corresponding to said determined location from memory and obtains from said cartographic data altitude information corresponding to said location, wherein said obtained altitude information is said supplemental altitude information input for deriving said correction factor.

2. The altimeter as set forth in claim 1, wherein said supplemental altitude information entered by a user via an external input on said altimeter.

3. A navigation device as set forth in claim 1, further comprising a GPS unit, wherein said GPS unit determines said supplemental altitude information.

4. A navigation device comprising:

a processor;

a memory having cartographic data, including altitude information, stored therein;

a GPS receiver;

an altimeter;

a barometric pressure sensor for sensing atmospheric from which said processor determines altitude information, wherein said altimeter is calibrated based upon supplemental altitude information retrieved from said altitude information stored in said memory and corresponding to a location of the navigaton device as determined, at least in part, by said GPS receiver.

5. A method comprising:

providing a memory for cartographic data,including altitude information, stored therein;

providing a GPS receiver;

providing an altimeter; and

calibrating said altimeter based upon supplemental altitude information retrieved from said memory and corresponding to a location of a navigation device as determined, at least in part, by said GPS receiver.