THE ROLE OF SATELLITE GEODESY AND GNSS TECHNOLOGIES IN THE RECONSTRUCTION OF GEODESIC NETWORKS

Abstract

The article discusses the theoretical and practical issues of reconstructing geodetic networks of large cities based on satellite geodesy and GNSS technologies using the example of the city of Fergana. First, urbanization processes, the densification of infrastructure facilities, and the limitations of traditional triangulation and leveling networks are analyzed, and the requirements for modern geodetic support are substantiated. Based on the analysis of foreign and domestic literature, the advantages of optimal design of GNSS networks, connection with global geocentric coordinate systems, CORS infrastructure, and hybrid (GNSS + ground-based geodetic instruments) approaches are shown. In the conditions of the city of Fergana, a three-stage geodetic network model (main base, densification, and working points) is proposed, and a conceptual methodology is developed for GNSS observation modes, network structure, and accuracy criteria. Statistical results show an increase in the number of geodetic points, a decrease in the mean square errors in plan and elevation by 50–60%, a sharp reduction in the duration of the measurement campaign and labor costs. The hybrid approach is justified as an optimal solution for ensuring accuracy and reliability in the conditions of the urban “city canyon”. The proposed approach, along with the modernization of the geodetic networks of Fergana, can serve as a methodological basis for other large cities of Uzbekistan.