Determination of environmental effects on GPS signals by using a geodesic receiver and several online PPP softwares

This paper describes the determination of ionospheric and tropospheric effects on satellite communications between Inmetro ground station and GPS constellation satellites This is made with the use of a geodesic receiver to collect data and with post processing softwares for PPP implementations. The data satellite communication link is used for time and frequency maintenance of Local Time Scale UTC (INXE) and for key comparison promoted by BIPM. Relative differences in the plasma density of ionosphere and the atmospheric conditions can be inferred from the different delays imposed to the propagating signal and there are some highlighted effect differences during daytime and nighttime signal behavior.