This study aims at the influence on the data acquisition with GPS receivers in altimetric determination. The altimetric survey is carried out through the method of static relative thread, using two GPS receivers of one frequency, at different times of occupation (30, 15, 10, 5 minutes), with a recording level of two seconds. The altitudes obtained with receivers GPS are compared with the altitudes determined by trigonometrical leveling with Total Station. The results showed that the periods of occupation lower than 30 minutes (15, 10 and 5 minutes) are also appropriated to obtain the centimetric differences for the analyzed altitudes. Considering the accuracy of the conventional topographical methods, this study demonstrates the possibility of the precise use of the Global Positioning System (GPS) in altimetric surveys, if modeling of the geoidal undulation is also used.
altimetry; system GPS; relative static method
