Online Positioning User Service (OPUS) Upgraded
OPUS, a service of NGS's Geodetic Tool
Kit, allows users to submit their GPS data
RINEX format to NGS, where the data will be
processed to determine a position using NGS computers
and software. Each RINEX file that is submitted will be
processed with respect to 3 known CORS.
NGS introduced a new version of OPUS (12/02/02) that
allows users to submit compressed GPS data (.ZIP, .zip,
.Z, .gz) as well as uncompressed GPS data. A still
newer OPUS version (06/01/03) allows users to select
one of more National or Cooperative GPS base stations
to be used in computing the positional coordinates.