Determination of TEC using GPS data from dual frequency receivers for the production of ionospheric maps to Brazil

Nowadays, one of the main drawbacks of the GPS accuracy for L1 users is the delay due to ionosphere. The error associated to the ionosphere depends on the Total Electron Content (TEC) in the ionospheric layer, that is influenced by several variables, including the solar cycle, the season, the local time, the geographical location of the receiver and the Earth’s magnetic field. The monitoring of the variation of TEC is important because it is the principal parameter that describes the ionospheric activity. Due to the characteristic dispersive of the ionosphere, the TEC has been computed using GPS data from double frequency receiver. In Europe and in North America, several research centers produce regional and global scale maps of the VTEC (Vertical TEC) using GPS data. In Brazil it can be used the GPS data from RBMC (Brazilian Network for Continuous Monitoring) for studying the behavior of TEC in the Brazilian area. The purpose of this paper is to produce maps of TEC of the ionosphere for Brazilian area using GPS data from double frequency receivers. The methodology and the strategy adopted for obtaining of the proposed results are also presented.