RINEX File Check and Repair¶
IIf one gets data of unknown quality, one should pass them at least once through a check procedure. If an output file is created it will be RINEX conform nevertheless the input was corrupt.
With gfzrnx this can be done via:
With -chk all formal checks are done on the input file.
The -kv (keep version) ensures the same output version as the input file (standard output format is the latest supported format).
The following modifications are done in the output file:
-
Update of observation types to really existing ones, overall empty observation types are removed.
- SYS / # / OBS TYPES
- # / TYPES OF OBSERV
-
Statistical information is added or updated in the file header.
- PRN / # OF OBS
- # OF SATELLITES
- INTERVAL
- TIME OF FIRST OBS
- TIME OF LAST OBS
Here is an example of an updated RINEX header information:
C 10 C1I C6I C7I D1I L1I L6I L7I S1I S6I S7I SYS / # / OBS TYPES
E 13 C1X C5X C7X C8X D1X L1X L5X L7X L8X S1X S5X S7X S8X SYS / # / OBS TYPES
G 20 C1C C2W C2X C5X D1C D1P D1W D2W L1C L1P L1W L2W L2X SYS / # / OBS TYPES
L5X S1C S1W S2C S2W S2X S5X SYS / # / OBS TYPES
J 19 C1C C1X C1Z C2X C5X C6L D1C L1C L1X L1Z L2X L5X L6L SYS / # / OBS TYPES
S1C S1X S1Z S2X S5X S6L SYS / # / OBS TYPES
R 13 C1C C1P C2C C2P D1C L1C L1P L2C L2P S1C S1P S2C S2P SYS / # / OBS TYPES
S 4 C1C D1C L1C S1C SYS / # / OBS TYPES
76 # OF SATELLITES
C01 2863 2863 2863 2863 2863 2863 2863 2863 2863PRN / # OF OBS
2863 PRN / # OF OBS
...
C14 1365 1363 1363 1365 1365 1363 1363 1365 1363PRN / # OF OBS
1363 PRN / # OF OBS
E11 900 895 893 899 900 900 895 893 899PRN / # OF OBS
900 895 893 899 PRN / # OF OBS
E19 1605 1601 1601 1603 1605 1605 1601 1601 1603PRN / # OF OBS
1605 1601 1601 1603 PRN / # OF OBS
G01 1189 1148 1181 1181 1189 1189PRN / # OF OBS
1148 1181 1181 1189 1181 1148PRN / # OF OBS
1181 1181 PRN / # OF OBS
...
G32 1247 1241 1247 1247PRN / # OF OBS
1241 1247 1241PRN / # OF OBS
PRN / # OF OBS
J01 2863 2863 2863 2863 2863 2863 2863 2863 2863PRN / # OF OBS
2863 2863 2863 2863 2863 2863 2863 2863 2863PRN / # OF OBS
2863 PRN / # OF OBS
R01 713 713 709 706 713 713 713 709 706PRN / # OF OBS
713 713 709 706 PRN / # OF OBS
...
R24 695 695 695 695 695 695 695 695 695PRN / # OF OBS
695 695 695 695 PRN / # OF OBS
S26 1973 1973 1973 1973 PRN / # OF OBS
...
S37 2863 2863 2863 2863 PRN / # OF OBS
30.000 INTERVAL
2014 8 17 0 0 0.0000000 GPS TIME OF FIRST OBS
2014 8 17 23 59 30.0000000 GPS TIME OF LAST OBS
...
The repair of a file is different concerning RINEX-2 and RINEX-3(4,...). Data values are not corrected! Via the repair operation, formally corrupt observation parts are omitted only.
-
RINEX-2
- A complete epoch block is removed in case of corrupted data detection.
-
RINEX-3 and higher
- A complete satellite block (line) is removed in case of corrupted data detection.
Navigation Data Epoch Filter¶
Use the -nav_epo_filter command line parameter to filter the navigation data input via epoch record checks. In this case, only nominal epochs are passed to the output file. Excluded records are given in the log table. Only epoch minutes and hours are checked at the moment. The following table shows valid hours and minutes per satellite system:
| Sat. System | Minutes | Hours (modulo) |
|---|---|---|
| C | 0 | 1 |
| E | 0,10,20,30,40,50 | 1 |
| G | 0 | 2 |
| R | 15,45 | 1 |
| J | 0 | 1 |
Meteo Data check/edit against NWM-Data¶
RINEX-meteo site data can be checked against a reference RINEX-file created from e.g. Numerical Weather Model (NWM) data (predicted or reprocessed). Two input files have to be given via the -finp command line parameter. The first file is the one to be checked, the second file is the reference file to be checked against.
The check limits for the different observation types are taken from the reference file "SENSOR MOD/TYPE/ACC" header records. Here is an example:
DNSXGFZ ERA5/ECMWF 10.0 PR SENSOR MOD/TYPE/ACC
DNSXGFZ ERA5/ECMWF 10.0 TD SENSOR MOD/TYPE/ACC
DNSXGFZ ERA5/ECMWF 100.0 HR SENSOR MOD/TYPE/ACC
Observations that exceed the difference limits are eliminated and don't go to the output file.
gfzrnx -met_nwm -finp POTS00DEU_R_20200010000_01D_05M_MM.rnx POTS00DEU_R_20200010000_01D_05M_MM.rnx_nwm -fout POTS00DEU_R_20200010000_01D_05M_MM.rnx_chk
By default, all observation types found in the reference file are used for the differences checks. To limit the tests to single observation types, they can be given via the -obs_types or -ot command line parameters.
The removed observations are documented in the log.
... | MESSAGE
...-+-----------------------------------------------------------...
... | MET_NWM: ignoring checks for obs. type -> PR
| MET_NWM: DELETED 2020-01-01 00:05:00.0000000 HR - -81.4( 97.4) exceeds limit of 100.0(178.8)
| MET_NWM: DELETED 2020-01-01 00:15:00.0000000 TD - 29.0( 2.6) exceeds limit of 10.0(26.4)
...