Patent ID: 7692583
Filing Date: 2010-04-06
Classification: G01C,G01S

Abstract:
1. A GPS position-measuring device for determining a position of a moving object by using GPS position measurement the GPS position-measuring device comprising: altitude obtaining means for obtaining non-GPS altitude information of the moving object; measuring means for determining (1) multiple GPS-satellite combinations from among multiple GPS satellites that can be tracked and (2) a GPS based three-dimensional position of the moving object for each of the multiple GPS-satellite combinations; difference extracting means for determining a difference in altitude between altitude information associated with the GPS based three-dimensional position and the non-GPS altitude information obtained by the altitude obtaining means for each of the multiple GPS-satellite combinations; and position determining means for comparing the extracted difference in altitude with a threshold value for each of the multiple GPS-satellite combinations, wherein when a single GPS-satellite combination for which the difference in altitude is less than or equal to the threshold value, the position determining means selects the single GPS-satellite combination, and when multiple GPS-satellite combinations for which the difference in altitude is less than or equal to the threshold value exist, the position determining means selects a minimum GPS-satellite combination for which the difference in altitude is a minimum from among the multiple GPS-satellite combinations that can be tracked, and a measurement position of the moving object is determined based on the GPS based three-dimensional position of the selected GPS-satellite combination.