Bernese GPS Software Version 5.0 - Bernese GNSS Software

4. Import and Export of External File Formats
files should, therefore, only be used within the Bernese GPS Software because a RINEX
file should contain raw measurements.
Either GNSS code and/or phase observations or ranges (SLR) may be converted (option
“Measurement types to save” in panel “RXOBV3 1”).
A station coordinate file may be updated or created based on the coordinates specified in
the RINEX headers by specifying a filename in option “Update coordinates”. Coordinates of
stations that are not included in this file are added with coordinate flag “R”.
Further options concerning the data selection are provided in panel “RXOBV3 2: Input Options
1” (Figure 4.2). Option “Satellite system to be considered” (GPS, GLONASS, or ALL) allows
to reduce the data amount by selecting only the observations you are interested in. In
addition you may specify an observation window in panel “RXOBV3 3: Observation Window”.
The default sampling rate within the IGS is 30 seconds but there may be stations which
have a higher sampling rate (e.g., 10 seconds). You may define the sampling for the Bernese
observation files in option “Sampling interval” in panel “RXOBV3 2: Input Options 1”. If the input
field is left empty or the value is set to 0 all observations from the RINEX file are converted.
The selected sampling rate is counted starting with an offset which you may specify in option
“Sampling offset to full minute”. If you, e.g., sample 10 seconds data to 60 seconds and specify
an offset of 10 seconds the observation epochs of the resulting Bernese observation file will
be 10 sec, 70 sec, 130 sec, etc. Note, that the current version of the Bernese GPS Software
does not process data with sampling higher than 1 Hz.
The panel “RXOBV3 4: Input Options 2” (Figure 4.3) addresses input options concerning signal
strength requirements, observation number, and antennas. The option “Minimum signal
strength” can be used to eliminate data with a low signal-to-noise ratio. According to the
RINEX format definition the signal-to-noise ratio is mapped into values from 0 to 9. A value
of 0 means either a bad observation (some RINEX converter use it like this) or an unknown
signal-to-noise ratio. If you use original RINEX files it is recommended to use all available
observations by accepting all available signal-to-noise ratios. Bad observations in the data
will be identified and excluded in the further processing.
You may, in addition to the above option, activate “Accept signal strength = 0” to keep data
with a signal strength of 0. This is recommended and makes sense if you wish to exclude
observations with low signal-to-noise ratio but want to process observations with unknown
quality.
If you have preprocessed the RINEX files with program RNXSMT (see Section 6.2) you have
to set option “Minimum signal strength” to 2 in order to eliminate bad observations (marked
by program RNXSMT with a signal strength of 1, see Section 6.2). You should also disable
option “Accept signal strength = 0” in this case.
Cycle slip flags from RINEX can be accepted by enabling the option “Accept cycle slip flags
from RINEX”. This option is available for processing zero difference phase observations. If
the RINEX files are already cleaned, e.g., by the program RNXSMT, then it is possible to
accept the cycle slip flags. Cycle slip flags from original RINEX files should, however, not be
accepted due to their potentially large number and because they will be reliably identified
in any case in the preprocessing procedures available in the Bernese GPS Software.
The exclusion of stations providing a small number of epochs is possible using “Minimum
number of epochs requested per file”. Note that stations may also be excluded by adding a cor-
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