Dual frequency receiver data, in general, are processed using the ionospheric free linear combination observable. In this dissertation, the ionosphere and troposhere effects will be introduced as unknown in the original observables (L1 and L2) and weighted from the a priori information available about their behavior. Therefore, the ambiguities will keep the integer characteristics, making easy the application of ambiguity resolution approaches, as the LAMBDA method. The first order ionospheric effects will be solved, in principle, epoch by epoch. Concerning to the second order effects, investigations will be carried out in order to analyze its behavior, aiming to define the time period in which it can be considered constant. For the tropospheric refraction, the delay model available at CPTEC, based on PNT (Numerical Weather Forecast), will be used to assess the a priori information. The definition of its appropriated weight will be part of the investigation. The topics involved in this project should guarantee the continuation of the state of the art research in the filed of GPS at FCT/UNESP.
News published in Agência FAPESP Newsletter about the scholarship: