Results obtained applying ionosphere maps for precise point positioning in the South American region

COSTA, S.; GENDE M.; BRUNINI C.; DA SILVA, N.; JOS DE MOURA, J.

Perugia

Congreso; IUGG XXIV General Assembly; 2007

International Union of Geodesy and Geophysics

Since 2005, the La Plata Ionosphere Model (LPIM) is used to routinely generate Vertical Total Electron Content (VTEC) maps byCPLAT (La Plata Processing Center) using about 50 GPS stations in South America. VTEC is modeled in modip latitude using alinear combination of undifferenced GPS carrier phase observables. A particular approach is used to solve the hardware-relatedbiases.Since 2003, the Instituto Brasileiro de Geografia e Estatstica (IBGE) collaborates to maintain the SIRGAS Reference Frame inSouth America, delivering weekly coordinate solutions using the same set of permanent stations that the CPLAT uses forcomputing ionosphere maps.This work presents two strategies for improving GPS coordinate solutions using ionosphere maps (regional and global) in SouthAmerica: to solve ambiguities in differential solution and to mitigate ionospheric bias in single frequency undifferenced solutions.