Abstract: According to the fact that it takes a lot of time to obtain high precision results by single epoch algorithm, three GNSS receivers are erected on a carrier. The distance between the receivers are measured in advance, and the attitude angles of the carrier are measured by a gyroscope. Thus, the distance and attitude constraints are added to the baseline adjustment. Then a relatively stable and accurate result is achieved. The experiment results show that the maximum deviations are less than 10mm in the east and north directions, 30 mm in the elevation direction. The accuracy of the result is improved by more than 15% compared to the result without distance and attitude constraints.

Key words: GNSS, attitude constraints, distance constraints, network adjustment