RINEX Extensions for Geostationary Satellites Version 2.10 Proposal for Some Modifications/Clarifications of RINEX Navigation Message Files for GEO Satellites Werner Gurtner, AIUB Norbert Suard, CNES Lou Estey, UNAVCO 19-Dec-2003 We propose the following modifications/clarifications in Chapter 9.2 of the document "RINEX The Receiver Independent Exchange Format Version 2.10" by W. GUrtner [1] 9.2 RINEX Navigation Message Files for GEO Satellites ----------------------------------------------------- - Rename "Message frame time" to "Transmission Time of Message". Clarify Beginning of the message - "Transmission Time of Message" is expressed in GPS seconds of the week (previously seconds of the day), clearer defined to be the beginning of the message transmission. - "The Transmission Time of Message" has to refer to the same GPS week as the "Epoch of Ephemerides". Adjust it by - or + 604800 seconds if necessary (which makes it lower than zero or larger than 604800, respectively). - "Health" shall be defined as follows Bits 0 to 3 equal to Health in Message Type 17 (MT17), bit 4 is set to 1 if MT17 health is unavailable, bit 5 is set to 1 if the URA index is equal to 15. (In the SBAS message definitions bit 3 of the health is currently marked as 'reserved'). In case of bit 4 set to 1, it is recommended to set to 1 bit 0 to 3. - "URA" Follow same convention for converting URA index to meters as with GPS. URA = 32767 meters if URA index = 15. - Replace CORR TO SYSTEM TIME by a GPS-like DELTA-UTC, supplemented with a satellite system designator, e.g. 0.133179128170D-06-0.107469588780D-12 518400 124O EGNOS 5 D-UTC A0,A1,T,W,S,U This type of optional record, if provided, could be present in the header as required regarding number of SBAS or change per SBAS. - "IODN" Clarify IODN data (Issue Of Data Navigation) as defined in RTCA DO229, Annex A for Message Type 9. The IODN is defined as the 8 first bits after the message type 9, called IODN in DO229A and DO229B and called "spare" in DO229C - BROADCAST ORBIT - 3 The fourth parameter (currently 'spare') will be defined as IODN References [1] W. Gurtner, "RINEX The Receiver Independent Exchange Format Version 2.10", ftp//igscb.jpl.nasa.gov/igscb/data/format/rinex210.txt ----|---1|0---|---2|0---|---3|0---|---4|0---|---5|0---|---6|0---|---7|0---|---8| +----------------------------------------------------------------------------+ | TABLE A15 | | GEOSTATIONARY NAVIGATION MESSAGE FILE - HEADER SECTION DESCRIPTION | +--------------------+------------------------------------------+------------+ | HEADER LABEL | DESCRIPTION | FORMAT | | (Columns 61-80) | | | +--------------------+------------------------------------------+------------+ |RINEX VERSION / TYPE| - Format version (2.xx) | F9.2,11X, | | | - File type ('H' = GEO nav mess data) | A1,39X | +--------------------+------------------------------------------+------------+ |PGM / RUN BY / DATE | - Name of program creating current file | A20, | | | - Name of agency creating current file | A20, | | | - Date of file creation (dd-mmm-yy hh:mm)| A20 | +--------------------+------------------------------------------+------------+ *|COMMENT | Comment line(s) | A60 |* +--------------------+------------------------------------------+------------+ *|D-UTC A0,A1,T,W,S,U | Corrections to transform the system time | |* | | to UTC | | | | A0,A1 Coefficients of 1-deg polynomial | 2D19.12, | | | A0 sec, A1 sec/sec | | | | CORR(s) = A0 + A1*DELTAT | | | | T Reference time for polynomial | I7, | | | (Seconds into GPS week) | | | | W Reference week number | I5, | | | (GPS week, continuous number) | | | | S EGNOS, WAAS, or MSAS ... | X,A5,X | | | (left-justified) | | | | U UTC Identifier (0 if unknown) | I2,X | | | 1=UTC(NIST), 2=UTC(USNO), 3=UTC(SU), | | | | 4=UTC(BIPM), 5=UTC(Europe Lab), | | | | 6=UTC(CRL), >6 = reserved for future | | +--------------------+------------------------------------------+------------+ *|LEAP SECONDS | Number of leap seconds since 6-Jan-1980 | I6 |* +--------------------+------------------------------------------+------------+ |END OF HEADER | Last record in the header section. | 60X | +--------------------+------------------------------------------+------------+ Records marked with * are optional +----------------------------------------------------------------------------+ | TABLE A16 | | GEOSTATIONARY NAVIGATION MESSAGE FILE - DATA RECORD DESCRIPTION | +--------------------+------------------------------------------+------------+ | OBS. RECORD | DESCRIPTION | FORMAT | +--------------------+------------------------------------------+------------+ |PRN / EPOCH / SV CLK| - Satellite number (PRN minus 100) | I2, | | | - Epoch of ephemerides (GPS) (Toe) | | | |(parameter To in DO 229, Message Type 9) | | | | - year (2 digits, padded with 0 | | | | if necessary) | 1X,I2.2, | | | - month,day,hour,minute, | 4(1X,I2), | | | - second | F5.1, | | | - SV clock bias (sec) (aGf0)| D19.12, | | | - SV relative frequency bias (aGf1)| D19.12, | | | - transmission time (sec of GPS week) | D19.12 | +--------------------+------------------------------------------+------------+ | BROADCAST ORBIT - 1| - Satellite position X (km) | 3X,4D19.12 | | | - velocity X dot (km/sec) | | | | - X acceleration (km/sec2) | | | | - health (0=OK) | | +--------------------+------------------------------------------+------------+ | BROADCAST ORBIT - 2| - Satellite position Y (km) | 3X,4D19.12 | | | - velocity Y dot (km/sec) | | | | - Y acceleration (km/sec2) | | | | - Accuracy code (URA, meters)| | +--------------------+------------------------------------------+------------+ | BROADCAST ORBIT - 3| - Satellite position Z (km) | 3X,4D19.12 | | | - velocity Z dot (km/sec) | | | | - Z acceleration (km/sec2) | | | | - IODN (Issue of Data Navigation, DO229, | | | | 8 first bits after Message Type if MT9) | | +--------------------+------------------------------------------+------------+ +------------------------------------------------------------------------------+ | TABLE A18 | | GEO NAVIGATION MESSAGE FILE - EXAMPLE | +------------------------------------------------------------------------------+ ----|---1|0---|---2|0---|---3|0---|---4|0---|---5|0---|---6|0---|---7|0---|---8| 2.10 H: GEO NAV MSG DATA RINEX VERSION / TYPE SBAS2RINEX 2.0 CNES 20-Oct-03 14:01 PGM / RUN BY / DATE COMMENT 0.133179128170D-06-0.107469588780D-12 518400 1240 EGNOS 5 D-UTC A0,A1,T,W,S,U 13 LEAP SECONDS This file contains navigation message data from a SBAS COMMENT (geostationary) satellite, here AOR-W (PRN 122 = # 22) COMMENT END OF HEADER 22 03 10 18 0 1 4.0-1.005828380585D-07 6.366462912410D-12 5.184420000000D+05 2.482832392000D+04-3.593750000000D-04-1.375000000000D-07 0.000000000000D+00 -3.408920872000D+04-1.480625000000D-03-5.000000000000D-08 4.000000000000D+00 -1.650560000000D+01 8.360000000000D-04 6.250000000000D-08 2.300000000000D+01 22 03 10 18 0 5 20.0-9.872019290924D-08 5.456968210638D-12 5.186940000000D+05 2.482822744000D+04-3.962500000000D-04-1.375000000000D-07 0.000000000000D+00 -3.408958936000D+04-1.492500000000D-03-5.000000000000D-08 4.000000000000D+00 -1.628960000000D+01 8.520000000000D-04 6.250000000000D-08 2.400000000000D+01 22 03 10 18 0 9 36.0-9.732320904732D-08 4.547473508865D-12 5.189510000000D+05 2.482812152000D+04-4.325000000000D-04-1.375000000000D-07 0.000000000000D+00 -3.408997304000D+04-1.505000000000D-03-5.000000000000D-08 4.000000000000D+00 -1.606960000000D+01 8.800000000000D-04 6.250000000000D-08 2.500000000000D+01 22 03 10 18 0 13 52.0-9.592622518539D-08 4.547473508865D-12 5.192110000000D+05 2.482800632000D+04-4.681250000000D-04-1.375000000000D-07 0.000000000000D+00 -3.409035992000D+04-1.518125000000D-03-3.750000000000D-08 4.000000000000D+00 -1.584240000000D+01 8.960000000000D-04 6.250000000000D-08 2.600000000000D+01 ----|---1|0---|---2|0---|---3|0---|---4|0---|---5|0---|---6|0---|---7|0---|---8| Contacts: ******** Werner Gurtner, AIUB E-Mail: werner.gurtner at aiub.unibe.ch Lou Estey, UNAVCO E-Mail: lou at unavco.org Norbert Suard, CNES E-Mail: Norbert.Suard at cnes.fr