Abstract:

The paper presents the causes that affecting the accuracy of positioning on the far seas and islands of Vietnam. In addition, the report also extracted some results that have been identi ed by GNSS technology on a number of points that coincided with Vietnam’s cadastral base networks. Based on points that already have coordinates (as consider to the known points) and their coordinates are measured and calculated in experimental time period, the systematic errors will be found. As a result of theoretical analysis and data processing, the following conclusions are determined: the huge limitations on accuracy of positioning in the East Sea of Vietnam in general and on the islands far from the mainland of Vietnam in particular. The accuracy of experimental site is only 3dm in the plane coordinate system; the accuracy is even lower in the Paracel and Spratly Islands areas. The above problems will be fully solved by a set of of scienti c solutions that have proposed by the authors at the end of this research. Depending on the practical situation, state agencies and authorities may choose one of such solutions to apply.