AVALIAÇÃO DE UM MODELO IONOSFÉRICO LOCAL EM REDES GPS: ESTUDO DE CASO PARA UM PERÍODO DE BAIXA ATIVIDADE SOLAR

Abstract

The goal of this study is to evaluate a local ionosphere model that uses a set of double-frequency GPS receivers for generating ionospheric corrections. These corrections allow single frequency receivers, located at the neighborhood of the network, to correct their raw observations from the ionospheric delay. The proposed model was evaluated as follows: according to the number of satellites observed simultaneously for all network stations; the observed and interpolated total electron content; and, the coefficients from a mathematical model that describe the error. The model was tested in single point positioning, where only code observations were used for data processing. Seven RBMC stations were chosen for experiments and the data were obtained from a period of low solar activity. The Bernese software was used for data processing and precise products (orbit and clocks) were used. The final solution is estimated using all observation epochs. For the experiments performed in this work, results from single point positioning show an improvement about 50% for the horizontal component and 74% for the height component, when they are compared with a processing without any ionospheric correction.