Precise Ephemeris Center of Mass and Antenna Phase Center Change Notice!!!
OMNIS Kalman Ephemeris Process to EPOCHA Ephemeris Process Transition
Starting with GPS Week 1677 (26 February 2012) the precise ephemeris, both Center of Mass and Antenna Phase Center, will be produced using the new EPOCHA Kalman process. The output files will only contain one change but will remain in the SP3 format.
The only change is that the EPOCHA data files are being computed at the five (5) minute interval rather than the original OMNIS 15 minute interval. This will cause an increase in file size by about three (3) times, both ascii and self-expandable executables. The data will be continued on and posted to the current calendar and current ftp directories. The older OMNIS Kalman 15 minute process data will be produced or paralleled through GPS Week 1682 (ending with the ephemeris on 7 April 2012) and be maintained in added ftp directories labeled with an appropriate identification during the transition time frame.
The NGA/GPS Division hopes that little to no confusion will occur during this transition. Any questions about the newer EPOCHA process or data can be addressed by using the contact information below.
Point of Contact: GPS Division
Phone Numbers:
Com. (314)676-9140/676-9142
DSN 846-9140/846-9142
Document last modified Wednesday, 04-Apr-2012 13:36:36 EDT
