The exploration of satellite clock and ephemeris error correction in wide area differential system

Abstract

Real time principle of wide area differential GPS (WADGPS) uses a generally inverted positioning method of four-dimensional solution of satellite clock and ephemeris corrections. Compared with the real time single point positioning, its positioning accuracy of this method is improved greatly, but the DOP of four-dimensional calculation is up to several hundred, under the error amplification effect of DOP, 1-3 m positioning precision level of WADGPS is difficult to breakthrough. To overcome the limit of DOP, the feasibility on large and small part decomposition of satellite clock and ephemeris error is analyzed, and optimal differential performances of the exploring two smallness correction methods: Small DOP and no DOP constraint, are analyzed, and they will be the foundation for further exploration. © 2012 Springer-Verlag.