Hi All, When using NRTK (VRS method) corrections are modelled by a network of CORS, then interpolated and broadcast to the rover as if it were from a non-existent nearby reference station. Correct me if I am wrong - A RINEX file is created for a specific coordinate near to the rover, e.g. for (1000, 2000, 100) as if there was a reference station there. My question is [B]how accurate is the RINEX file created for the chosen location? What kind of spatial error is involved in its creation compared to data actually collected at that coordinate? [/B] Any help or references to relevant research would be much appreciated! Thanks, Tom