Bernese GPS Software Version 5.0 - Bernese GNSS Software

14. Clock Estimation
cessed if CCRNXC retains the reference clock from one of the input files for the output
file (option “Retain the reference clock from an input file” in panel “CCRNXC 4: Select Program
Functions, Program Output”, see Section 14.3.4 for more details).
For the clocks in the output file a summary table is included in the program output if the
option “Statistic about the resulting clocks” in panel “CCRNXC 4: Select Program Functions, Program
Output” is enabled:
STATISTICS ON THE CLOCKS IN THE OUTPUT FILE
-------------------------------------------
# per file rms of poly. fit (ns)
Clock name out 001 n = 0 n = 1 n = 2
-------------------------------------------------------------------
PTBB 14234M001 288 288 0.280 0.000 0.000
BRUS 13101M004 288 288 0.374 0.032 0.028
MATE 12734M008 244 244 17.911 0.120 0.069
...
G20 78 78 1.326 0.119 0.114
G16 66 66 54.257 0.129 0.126
G14 95 95 8.440 0.190 0.159
...
The table contains an entry for each station and satellite clock included in the output file.
The number of epochs in the output file (column out) as well as in each of the input clock
RINEX files (in this example only one input file 001 is available) is listed (Remember: If
a time window was specified for the processing the epochs outside the time window are
ignored in the input clock RINEX files). The third part of this summary table reports the
RMS of a low-order polynomial fitted to the clock values in the output file: For n = 0 only
an offset is modeled, for n = 1 a linear clock model is applied, and for n = 2 a quadratic
model is used to fit the clocks. The clocks may be sorted within the table (separately for
station and satellite clocks) by the name (ALPHA) or by the RMS of the linear clock model
listed in column n = 1 (SIGMA), see option “Sort order for clock statistics” in panel “CCRNXC 4:
Select Program Functions, Program Output”.
14.3.3 Combining Clock RINEX Files
The input clock RINEX files may at equal epochs refer to different reference clocks. To
transform all files to the same reference, offsets between the individual files have to be
estimated. This is done epoch-wise by a least-squares adjustment. You may select in the
input panel “CCRNXC 3: Options for Clock RINEX File Combination” whether station and/or
satellite clocks shall be used for the offset computation. In addition, a threshold for the
maximum allowed residual of a clock contributing to the offset estimation may be specified
(see Figure 14.6).
The RMS of the estimation and the covariance information for each offset can be interpreted
as a measure for the consistency of the clock RINEX files for the particular epoch. This
information is written to the program output for each epoch if the “Detailed report on clock
combination” in panel “CCRNXC 4: Select Program Functions, Program Output” is enabled:
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