Abstract

The current terrestrial measurements in the combing terrestrial – GNSS network is mainly horizontal angle measurements and slant distance measurement. Becausethe accuracy of measuring angle of the modern total station is getting betterand better, approximate ± 1'', it is possible to measure vertical angle inorder to increase the accuracy of determining z - coordinate for the combining terrestrial – GNSS spatial network. However, in the process of measuring vertical angle, it is inevitable that many sources of error, especially systematic errors. In order to increase the accuracy of determining z - coordinate in thecombining terrestrial – GNSS spatial network, in this the article, we presented the algorithm to detect systematic errors in measuring vertical. The study ofthis adjustment algorithm has both theoretical and practical been successfully implemented and presented in the article.