Precise point positioning : studio sulle accuratezze e precisioni ottenibili

The possibility to obtain precise solution, without using a phases differential approach, which is possible only in a same-time GPS acquisition, could be a interesting technology for particular condition or for specific goals. PPP (Precise Point Position) solutions accuracy is improving during years, cause to a more accurate estimate of fundamental parameters, such as satellite orbits, clocks, iono-tropospheric models, etc... Now, GPS daily sessions can provide a centimetric accuracy. This experience come up from the requirement to obtain a precise position of GPS points with an inter-distance of about 100 kilometers from a GPS base stations. This experience is made to evaluate the real accuracy of this methodology, varying observation windows, in two different places (Italy and Antarctica). Data comes from Mario Zucchelli permanent station (Terra Nova Bay, Antarctica) and from several GPS stations in Emilia-Romagna region. All processing is done using GIPSY-OASIS II (Jet Propulsion Lab, NASA).