Document Type : Research Paper

Author

• Abbasali Salehabadi (Translator)

Master of Geodesy

Abstract

By introducing GPS into the global arena and increase in its applications, the basic concepts of geodetic science and surveying have changed. GPS is capable of a relatively fast and accurate determination of position in any weather conditions. Working with it is economical and cost-effective. On the other hand, the difference in coordinates taken from GPS is often more important than the equivalent coordinates extracted from drawn or digital maps. The map data contains the long-standing problems arising from determination of planimetric base-level, the image system, surveying
operations and their common errors. But these are now better characterized by the coordinates derived from GPS. The GPS is relatively inexpensive, efficient and flexible and determines the three-dimensional position of points with high precision. This technique can be used effectively in navigation, surveying and geodesy. However, there are still some very important issues in combining GPS coordinates with positional information from other methods that are troublesome for us. These issues will become more apparent when the above-mentioned position information is extracted from a digital map database. In general, such information is derived from digitization of linear maps. Therefore, of such positions with the position of the GPS involves in a series of the resulting positions are affected by a variety of errors in the process. Any combination specified computational steps. These computational steps’ purpose is to determine the proper estimation and verification of data between two sets of position presented.