Ambiguity resolution at network based positioning

Abstract

The correct ambiguity resolution in GNSS (Global Navigation Satellite System) positioning is a difficult task for medium and long baselines. But, in order to realize high accuracy positioning (centimetric), it is indispensable a correct ambiguity resolution. In this research, the main goal is to work with ambiguity resolution for network-based positioning. Network-based positioning has been widely used by international scientific community due density and availability of GNSS reference station data, and, mainly, due to high accuracy obtained by this method. Stations high density also facilitates the ambiguity resolution, which does note occurs in Brazil, where the medium distances among reference stations, even for GNSS/SP network, is about 200 km. Concerning studies related to network-based positioning in Brazil, this kind of positioning, using scientific software, started with the advisor of this proposal (Doctorate - FAPESP Process: 2003/12771-0; Pos-doctorate - FAPESP Process: 2008/06499-9) during her doctorate and post-doctorate studies. During the development of network-based system it was implemented a method without ambiguity resolution. Just initial studies were accomplished concerning ambiguity resolution. Therefore, this research idea is to implement a robust method of GNSS ambiguity resolution, according Brazilian atmospheric conditions, there are very peculiar. So, we intend to develop a more efficient method for network-based in Brazil.