Bernese GPS Software Version 5.0 - Bernese GNSS Software

6. Data Preprocessing
6.6.3 Detect Misbehaving Stations and Satellites (RESCHK)
For a robust automated processing it is essential to have a tool at hand to detect and exclude
misbehaving stations, e.g., stations with strange data that cannot be handled properly in
the preprocessing programs of Version 5.0 of the Bernese GPS Software – at least not with
the default settings used in an automated processing. Also satellites whose orbits are not
modeled sufficiently well (e.g., due to a repositioning event) should be detected and excluded
from the processing.
The Bernese GPS Software Version 5.0 provides such a tool with program RESCHK (”Menu
>Service>Automated processing>Detect misbehaving stations/satellites”). It is able to analyze the summary
file of the program RESRMS and to detect events in the solution. The program handles only
one problem type per run, following the priority
(1) MANEUVER DETECTED FOR SATELLITE(s),
(2) BAD STATION(S) DETECTED,
(3) BAD SATELLITE(s) detected,
(4) SATELLITE(s) W/O OBSERVATIONS detected, or
(5) NO SPECIAL EVENTS FOUND IN THIS SOLUTION.
The result is reported by the above strings in the program output.
Keep in mind that the identification of “misbehaving” stations or satellites may also indicate
that your settings of the preprocessing input options are not optimal!
Bad Station Detection
A station or baseline is assumed to be “bad” if the total RMS in the last column of the
RESRMS residual summary file exceeds a user specified threshold (“Maximum allowed overall
RMS error” in panel “RESCHK 2.1: Detection of Bad Stations”).
In the case of baseline residuals the “bad” stations are extracted in the following way from
the list of “bad” baselines:
• If a station from a “bad” baseline is found in any “good” baseline, too, the station
is assumed to be “good”. If both stations of a “bad” baseline are set back to “good”
this may indicate a problem in preprocessing of the baseline (e.g., options for program
MAUPRP).
• If a station is found in only one baseline the other station of the baseline is checked.
If this other station is found in “bad” baselines only, the first station is marked as
“good”. If the second station is “good”, the first station is marked as “bad” (it is
assumed that a “bad” baseline contains only one “bad” station).
The option “Maximum number of stations to delete” provides a limit for the number of stations
to be deleted per program run. If more “bad” stations are found the stations with the
biggest total RMS errors are selected. If you analyze baseline residuals the total RMS of a
station is computed as the mean RMS over all baselines containing the station. If the total
RMS of at least one station in the zero-difference case exceeds the limit specified in option
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