GNSS: investigations and applications in geodetic positioning, in studies related to the atmosphere and precision agriculture

Abstract

The central theme of this project is GNSS. As it is a multidisciplinary technology, to enhance the knowledge on this theme it is important to develop project involving specialist of the several disciplines related with. The project involves researchers from Geodesy, aiming to develop algorithms and methodologies for several applications, among them those that can be applied in the Precision Farming, area that is also involved in the project, as well as in the Cartography and Cadastre. Therefore, a network of GNSS will be set up, which will provide the necessary infra-structure to the project, besides opening perspectives of using and investigating in other areas, once the data will be available to the public. As a product from Geodesy, the zenithal tropospheric delay will be integrated with meteorological measurements on the surface and mean average temperature model to provide the Integrated Water Vapor (IWV), which will be assimilated in the numerical weather prediction model, contributing with weather forecast. By other hand, with a good weather forecast model, the Meteorology can return to Geodesy good values of tropospheric zenithal delays, contributing with GNSS real time applications, including navigation. GNSS has its signals affected by the ionosphere. As a result, GNSS can be used to study the ionosphere. Using a network of double frequency receivers, one can develop model to describe the ionosphere behavior, and to generate an ionosphere field, allowing applying at other sites in the network. Another important element for using GNSS is a geoidal model, which must have accuracy compatible with the altitude system used. The integration of GNSS, geopotential models and gravity measurements are the necessary elements for its production, topic that also make part of the project, together with sea level monitoring, origin of the height systems. Several aspects of the themes presented so far will be investigated in this project, searching when possible, the sinergy among them, in such a way to provide sustainability to the project as a whole and to put São Paulo State in the vanguard in the field of investigations related to GNSS. (AU)