초록 ▼

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 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.

대표청구항 ▼

1. A method of calibrating an altimeter, said method comprising:calculating altitude based upon sensed barometric pressure; calculating altitude based upon GPS; and comparing said calculated barometric-pressure based altitude with said calculated GPS based altitude and, when said calculated barometr

1. A method of calibrating an altimeter, said method comprising:calculating altitude based upon sensed barometric pressure; calculating altitude based upon GPS; and comparing said calculated barometric-pressure based altitude with said calculated GPS based altitude and, when said calculated barometric-pressure based altitude differs from said calculated GPS based altitude by at least a selected amount, then selecting not to rely upon said calculated barometric-pressure based altitude.