iGage iG9 User Manual
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In some areas there is a risk that if a single CORS site is unavailable, your OPUS-RS job will not be
processed. Caution and planning are suggested for OPUS-RS jobs.
OPUS-Projects
OPUS Projects is a relatively new online tool. Its use requires taking a NGS training class, but the
invested time is well worth it as OPUS-Projects will allow you to combine the observation files from
multiple receivers and multiple sessions.
There is an excellent article an
d video describing OPUS Projects in the October 2013 ‘American
Surveyor’ magazine. Search for “OPUS
-
Projects: The Next Revolution in GPS” to find a full resolution
PDF.
OPUS Error Messages and Failures
There are lots of possible error messages when processing OPUS solutions. It is our experience that
almost all errors fall into a single category:
“There is not enough nearby CORS data to effectively process your occupation…
yet
.”
In general, the solution is nearly always the same:
“Wait until more data become
s available and resubmit your job
.”
If you are processing OPUS-RS jobs in an area with very few CORS stations, and one CORS station
was offline, waiting will not help. OPUS-Static is the solution for locations where OPUS-RS is not
dependable.
CORS stations can report observations hourly or daily. In some areas (typically UNAVCO PBO sites)
most of the sites report once at the end of each day (GMT.) So, data that is needed to process your
job is not available until 4:00 am GMT on the day after you collect data.
The Download tool allows you to submit jobs to alternative services like AUSPOS and RTX. Typically,
these alternative services closely match OPUS.
If you submit an observation to OPUS and nothing comes back, check your SPAM folder. OPUS
solutions are regularly misidentified as spam.
OPUS is sometimes unavailable or takes longer than other times.
Interpreting OPUS Results
When you receive an OPUS solution by email from the NGS, it will look something like this:
USER: [email protected] DATE: May 06, 2014
RINEX FILE: p4490900.14o TIME: 16:08:35 UTC
SOFTWARE: page5 1209.04 master93.pl 022814 START: 2014/03/31 00:00:00
EPHEMERIS: igs17861.eph [precise] STOP: 2014/03/31 23:59:00
NAV FILE: brdc0900.14n OBS USED: 45735 / 47174 :97%
ANT NAME: TRM29659.00 SCIT # FIXED AMB: 162 / 171 :95%
