RINEX Extensions to Handle Clock Information ******************************************** Jim Ray, US Naval Observatory Werner Gurtner, University of Berne (Initial version, 27 August 1998; version 2.00 final update, 16 June 1999) (Version 3.02, 02 September 2010) -. SUMMARY OF CHANGES IN VERSION 3.00 and later The changes introduced in version 3.00 are mostly to be consistent with RINEX 3.00 and to recognize the use of other Global Navigation Satellite Systems (GNSSs) besides the Global Positioning System (GPS): a. "RINEX VERSION / TYPE" header changed to 3.00 and to add satellite system designator. b. "PGM / RUN BY / DATE" header date format elaborated. c. "SYS / # / OBS TYPES" header added. d. Added Galileo and Satellite-Based Augmentation System (SBAS) satellite designators in Section 5. e. "TIME SYSTEM ID" header added. f. The satellite antenna phase center offset information has been moved from a mandatory comment to the "SYS / PCVS APPLIED" header and now includes the associated phase center variation information also. It is expected that an external file will be referenced. g. "SYS / DCBS APPLIED" header added. h. Capability of handling inter-system timing biases and new intra-lab biases (possibly as new types of CR data record) are under consideration but not yet adopted. i. In version 3.01 a few cases where "GPS time" was specified have been corrected to read "specified system time". j. In version 3.02 satellite codes for the QZSS ("Jnn") and COMPASS ("Cnn") systems as well as the QZSS system time designator ("QZS") have been added. 0. INTRODUCTION Thus far, the IGS has produced clock results only for the GPS satellites and these are tabulated and distributed at the 15-minute intervals used in the sp3 orbit ephemerides files. There is much interest in increasing the satellite clock interval to 30 seconds (e.g., to overcome SA effects on interpolation) and also in producing station clock results (at some appropriate interval, probably 5 minutes). In principle, the sp3 format could continue to be used for both of these extensions, but it would be wasteful considering that the vast majority of the file space is set aside for orbit information. Also, the variety of other clock information that also needs to be exchanged does not lend itself to the sp3 format. Alternatively, the IGS could devise a new format specifically for distributing clock information. It does not appear that the timing community already uses a standard data format that is well suited for the IGS needs. 1. CLOCK DATA TYPES At the level of monitoring and reporting data from a specific GPS station (or more generally, a "receiver", which could include low Earth-orbiting satellites and other non-stationary platforms) the following types of observations can be expected: calibration data (CR): time delay measurements between a GPS receiver and some external reference point (e.g., local master clock) discontinuity data (DR): a phase-tracking GPS receiver (e.g., AOA TurboRogue) maintains an internal clock that sometimes will reset itself; in principle, there may be methods to monitor such changes which could then be logged as a relative change in clock state From analysis of GPS data, the results for an ensemble of receiver and satellite clocks can be determined differentially. Normally, all clock values are estimated relative to a single clock being held fixed as a reference. Alternatively, a linear combination of the estimated clocks can be held fixed to some apriori value (normally, zero). Either way, all the clock values can be re-aligned after estimation to remove the effect of the particular choice of reference clock, which can change for each data analysis arc. Such re-alignment is most commonly done using broadcast GPS time for the satellites as an underlying timescale, typically fitted to a low-order polynomial. In any case, the data are: analysis data (AR,AS): results from GPS phase/pseudorange data analysis for a network of station/receiver (AR) and satellite (AS) clocks, all relative to a fixed reference clock (or ensemble) adopted in the analysis If a timescale re-alignment has been applied (e.g., to GPS time), then the analysis reference clock will have non-zero values (but should still be reported as the reference in the header records) and these must be reported together with all other estimated clocks in the clock data records. In this case, the method of re-alignment should be described in the header comment records. In addition, the broadcast clocks of the satellites can be monitored and compared to a laboratory standard: monitor data (MS): broadcast values for satellite clocks as compared with a laboratory standard via monitor receivers (usually timing receivers) 2. FORMAT TYPES AND FILE NAMING Following established practice, the receiver-specific data ("CR" and "DR") could be reported using an extension of the RINEX format while the analysis data ("Ax" and "MS") could be reported using an extension to a standard product format, such as SINEX. However, since all of these data types are related and probably need similar format requirements, it seems more economical to consider a single file format type suitable for all. RINEX seems the most appropriate file type, even though it is not normally used for analysis products. When it becomes feasible and necessary to include clock estimates with other analysis products, then suitable formats can be incorporated into SINEX. Until then, it is suggested that a RINEX format extension be used for all clock/timing results. Normally, "CR" and "DR" data types would be collected at the stations, files would be prepared at the data centers, and the files would flow to the Global Data Centers named as: for calibration data (CR) & discontinuity data (DR) --------------------------------------------------- ssssdddf.yyC ssss: 4-character station/receiver name designator ddd: day of the year of first record f: file sequence number within day 0: file contains all the existing data of the current day yy: year C: file type "C" for clock information The suffix "C" would be a new RINEX file type. Normally, data would be compiled into files by each 24-hour day (according to the specified time system). The analysis results "AR", "AS", and "MS" would be formed at IGS Analysis Centers or by IGS/BIPM Pilot Project analysis groups and would normally include results for a number of stations/receivers and/or satellites. These files would be named as: for analysis data (Ax) & monitor data (MS) ------------------------------------------ cccwwwwd.clk ccc: 3-character analysis center name designator wwww: GPS week number d: day within GPS week (0 - 7) clk: suffix to identify clock information product files Files could be either daily (d = 0,...,6) or weekly (d = 7). However, despite the file names, a single format for the contents would apply for all data types. 3. NUMERICAL PRECISION All timing quantities (units sec, sec/sec, sec/sec**2) are reported in exponential format with a precision of 12 decimal places. 4. CLOCK DISCONTINUITIES Clock discontinuities (in bias, rate, and/or acceleration) could be reported in either of two ways. If monitored in situ and logged, these could be reported as "DR" data types in .yyC station files. If detected in data analysis, these can be reported in .clk files as two "AR" data records for the same station at the same epoch but with two different sets of clock values. 5. RECEIVER AND SATELLITE NAMES Since the clock data are normally used in conjunction with data analysis results (even for the calibration and discontinuity data types), it is most convenient to use naming conventions for the receivers and satellites which correspond to the same names used in analyses. In order to ensure uniqueness and complete identification, it is also necesssary to supply the receiver ID number (for fixed terrestrial receivers, the DOMES number issued by the Terrestrial Frame Section of the IERS). Thus, receivers should be identified by: Station names: IGS official 4-character receiver name designator Station number: DOMES number (or other unique identifier) For satellite names, the following designations are used in RINEX: Satellite names: 3-character string: "Gnn": nn is the PRN number for GPS satellites "Rnn": nn is the slot number for GLONASS satellites "Enn": nn is the PRN number for Galileo satellites "Cnn": nn is the PRN number for COMPASS satellites "Jnn": nn is PRN-192 where PRN is the QZSS satellite PRN number "Snn": nn is PRN-100 for Satellite-Based Augmentation System (SBAS) payloads If other satellite transmitters become available with suitable GPS- or GLONASS-like signals, such as the geostationary platforms currently being considered, then they can also be included using future RINEX naming conventions. 6. RINEX CLOCK FORMAT DEFINITIONS AND EXAMPLES The header recorders should be included in the order indicated, when required. The records below marked with * are optional. It is recommended that each record be read into a blank buffer string and then the information can be decoded afterwards from the buffer. Header and data records are limited to 80 characters. If more than bias and bias sigma are reported, a continuation line must be used. A data file must begin with the header records. Data records begin immediately after the "END OF HEADER" record and complete the remainder of the data file. +----------------------------------------------------------------------------+ | TABLE A15 | | CLOCK DATA FILE - HEADER SECTION DESCRIPTION | +--------------------+------------------------------------------+------------+ | HEADER LABEL | DESCRIPTION | FORMAT | | (Columns 61-80) | | | +--------------------+------------------------------------------+------------+ |RINEX VERSION / TYPE| - Format version: 3.00 | F9.2,11X, | | | - File type ("C" for Clock Data) | A1,19X, | | | - Satellite System: G: GPS | A1,19X | | | R: GLONASS | | | | E: Galileo | | | | C: COMPASS | | | | J: QZSS | | | | S: SBAS payload | | | | M: mixed | | | | | | +--------------------+------------------------------------------+------------+ |PGM / RUN BY / DATE | - Name of program creating current file | A20, | | | - Name of agency creating current file | A20, | | | - Date and time of file creation | | | | Format: yyyymmdd hhmmss zone | A20 | | | zone: 3-4 char. code for time zone. | | | | UTC recommended! | | | | LCL if local time with unknown | | | | local time system code | | | | | | +--------------------+------------------------------------------+------------+ *|COMMENT | Comment line(s) | A60 |* | | | | | | While comments are generally optional, | | | | they must be included for the following | | | | information: | | | | | | | | TIMESCALE RE-ALIGNMENT | | | | ---------------------- | | | | If estimated clock values have been | | | | uniformly shifted in timescale, e.g., to | | | | GPS time, the method applied should be | | | | noted here. In addition, non-zero clock | | | | values should be reported in the clock | | | | data records for the analysis reference | | | | clock, corresponding to the alignment | | | | correction applied to all the receiver | | | | and satellite clocks. The analysis | | | | reference clock should still be listed | | | | as "ANALYSIS CLK REF" even though it | | | | will have non-zero values. | | | | | | | | * REQUIRED for data types "Ax", if | | | | applicable | | | | | | +--------------------+------------------------------------------+------------+ |SYS / # / OBS TYPES | - Satellite system code (G/R/E/S) | A1, | | | - Number of different observation types | 2X,I3, | | | used for the specified satellite system| | | | - Observation descriptors: | 13(1X,A3) | | | - Type | | | | - Band | | | | - Attribute | | | | | | | | Use continuation line(s) for more than | 6X, | | | 13 observation descriptors. | 13(1X,A3) | | | | | | | In mixed files: Repeat for each | | | | satellite system. | | | | | | | | The following observation descriptors | | | | are defined in RINEX Version 3.00: | | | | | | | | Type: C = Code / Pseudorange | | | | L = Phase | | | | D = Doppler | | | | S = Raw signal strength | | | | I = Ionosphere phase delay | | | | X = Receiver channel numbers | | | | Band: 1 = L1 (GPS,SBAS) | | | | G1 (GLO) | | | | E2-L1-E1 (GAL) | | | | 2 = L2 (GPS) | | | | G2 (GLO) | | | | 5 = L5 (GPS,SBAS) | | | | E5a (GAL) | | | | 6 = E6 (GAL) | | | | 7 = E5b (GAL) | | | | 8 = E5a+b (GAL) | | | | 0 for type X (all) | | | | Attribute: | | | | P = P code-based (GPS,GLO) | | | | C = C code-based (SBAS,GPS,GLO) | | | | Y = Y code-based (GPS) | | | | M = M code-based (GPS) | | | | A = A channel (GAL) | | | | B = B channel (GAL) | | | | C = C channel (GAL) | | | | I = I channel (GPS,GAL) | | | | Q = Q channel (GPS,GAL) | | | | S = M channel (L2C GPS) | | | | L = L channel (L2C GPS) | | | | X = B+C channels (GAL) | | | | I+Q channels (GPS,GAL) | | | | M+L channels (GPS) | | | | W = based on Z-tracking (GPS) | | | | (see text) | | | | Z = A+B+C channels (GAL) | | | | blank : for types I and X (all) | | | | or unknown tracking mode | | | | | | | | All characters in uppercase only! | | | | | | | | Units : Phase : full cycles | | | | Pseudorange : meters | | | | Doppler : Hz | | | | SNR etc : receiver-dependent | | | | Ionosphere : full cycles | | | | Channel # : See text | | | | | | | | Sign definition: See RINEX text. | | | | The attribute can be left blank if not | | | | known. See RINEX text! | | | | | | | | NOTE FOR CLOCKS: | | | | Not all possible observation types are | | | | relevant for clock analysis results. | | | | List only those used for clocks. The | | | | code observables that are converted to | | | | a different form for consistency should | | | | be listed as equivalent to the converted | | | | type, not the original type. | | | | | | | | * REQUIRED for data types "Ax" & "MS" | | | | | | +--------------------+------------------------------------------+------------+ |TIME SYSTEM ID | - Time system used for time tags: | 3X,A3 | | | - GPS = GPS system time | | | | -> steered to (TAI - 19 s) | | | | - GLO = GLONASS system time | | | | -> steered to UTC | | | | - GAL = Galileo system time | | | | -> steered to GPS time | | | | - QZS = QZSS system time | | | | -> steered to GPS time | | | | - UTC = Coordinated Universal Time | | | | - TAI = International Atomic Time | | | | Compulsory in mixed GNSS files | | | | Defaults: GPS for pure GPS files | | | | GLO for pure GLONASS files | | | | GAL for pure Galileo files | | | | (none) for pure COMPASS files | | | | GPS for pure QZSS files | | | | (none) for pure SBAS files | | | | | | +--------------------+------------------------------------------+------------+ *|LEAP SECONDS | Number of leap seconds since 6-Jan-1980 | I6 |* | | as transmitted by the GPS almanac. | | | | Recommended for mixed GNSS files. | | | | | | +--------------------+------------------------------------------+------------+ |SYS / DCBS APPLIED | - Satellite system (G/R/E/S) | A1, | | | - Program name used to apply | 1X,A17, | | | differential code bias corrections | | | | - Source of corrections (URL) | 1X,A40 | | | | | | | Repeat for each satellite system. | | | | | | | | No corrections applied: Blank fields or | | | | record not present | | | | | | | | * REQUIRED for data types "Ax", if | | | | applicable | | | | | | +--------------------+------------------------------------------+------------+ |SYS / PCVS APPLIED | - Satellite system (G/R/E/S) | A1, | | | - Program name used to apply | 1X,A17, | | | phase center variation (PCV) and | | | | phase center offset (PCO) corrections | | | | - Source of corrections (URL) -- give | 1X,A40 | | | filename (preferably URL) containing | | | | values used in the data analysis for | | | | the vector antenna phase center | | | | offsets, PCOs (from the center of mass | | | | to the antenna phase center for each | | | | satellite; from the antenna reference | | | | point (ARP) to the antenna phase | | | | center for a tracking antenna) and the | | | | associated phase center variations | | | | (PCVs) as a function of viewing angle. | | | | | | | | Repeat for each satellite system. | | | | | | | | No corrections applied: Blank fields or | | | | record not present | | | | | | | | * REQUIRED for data types "Ax", if | | | | applicable | | | | | | +--------------------+------------------------------------------+------------+ |# / TYPES OF DATA | - Number of different clock data types | I6, | | | stored in the file | | | | - List of clock data types | 5(4X,A2) | | | | | | | The following clock data types are | | | | defined in RINEX Version 2: | | | | | | | | "AR": Data analysis results for receiver | | | | clocks derived from a set of | | | | network receivers and satellites | | | | wrt to a reference clock fixed in | | | | the analysis | | | | "AS": Data analysis results for satellite| | | | clocks derived from a set of | | | | network receivers and satellites | | | | wrt to a reference clock fixed in | | | | the analysis | | | | "CR": Calibration measurements for a | | | | single GNSS receiver wrt an | | | | external local reference clock | | | | "DR": Discontinuity measurements for a | | | | single GPS receiver | | | | "MS": Monitor measurements for the | | | | broadcast satellite clocks wrt a | | | | standard timescale | | | | | | +--------------------+------------------------------------------+------------+ |STATION NAME / NUM | - 4-character receiver name designator | A4,1X, | | | - Unique receiver identifier, | A20,35X | | | preferably the DOMES number for | | | | fixed stations | | | | | | | | * REQUIRED for data types "CR" & "DR" | | | | | | +--------------------+------------------------------------------+------------+ |STATION CLK REF | Unique identifier for external | A60 | | | reference clock being used as the | | | | standard for calibration | | | | | | | | * REQUIRED for data type "CR" | | | | | | +--------------------+------------------------------------------+------------+ |ANALYSIS CENTER | Name of Analysis Center | | | | - 3-character IGS AC designator | A3,2X, | | | - Full name of Analysis Center | A55 | | | | | | | * REQUIRED for data types "Ax" & "MS" | | | | | | +--------------------+------------------------------------------+------------+ |# OF CLK REF | - Number of analysis clock references | I6,1X, | | | (satellite or receiver clocks) listed | | | | under "ANALYSIS CLK REF" | | | | - Start epoch (in the specified time | | | | system): | | | | year (4 digits),month,day,hour,min, | I4,4I3, | | | second | F10.6, | | | [default: blank start and stop times | | | | imply single "ANALYSIS CLK REF" | | | | applies for entire file] | | | | - Stop epoch (in the specified time | | | | system): | 1X, | | | year (4 digits),month,day,hour,min, | I4,4I3, | | | second | F10.6 | | | [default: blank start and stop times | | | | imply single "ANALYSIS CLK REF" | | | | applies for entire file] | | | | | | | | NOTE: Multiple groups of "# OF CLK REF" | | | | "ANALYSIS CLK REF" records can be used | | | | for changes in analysis clock reference | | | | within a single analysis file. | | | | | | | | * REQUIRED for data types "Ax" | | | | | | +--------------------+------------------------------------------+------------+ |ANALYSIS CLK REF | List of the analysis clock references | | | | (repeat for each reference clock | | | | enumerated in the previous record) | | | | - Name of the receiver or satellite | A4,1X, | | | used as the fixed reference in data | | | | analysis | | | | - Unique identifier for reference | A20,15X, | | | clock (if a receiver), preferably | | | | the DOMES number for fixed stations | | | | - Optionally a non-zero value for the | E19.12,1X | | | the apriori clock constraint can be | | | | provided (unit: seconds). | | | | | | | | NOTE: If all analysis clock estimtes are | | | | re-aligned (e.g., to broadcast GPS time) | | | | then the fixed (reference) clock(s) will | | | | have non-zero values corresponding to | | | | the alignment corrections applied to all | | | | other clocks. The non-zero clock values | | | | for the reference clock must be reported | | | | in the clock data records together with | | | | the other clock values, but the reference| | | | clock should still be listed here. The | | | | method of re-alignment should be | | | | described in header comment records. | | | | | | | | * REQUIRED for data types "Ax" | | | | | | +--------------------+------------------------------------------+------------+ |# OF SOLN STA / TRF | - Number of receivers included in the | I6,4X, | | | clock data records (including the | | | | analysis reference clock even if it | | | | has zero values and is not given in | | | | the data records) and listed in the | | | | following header records | | | | - Terrestrial reference frame or | A50 | | | SINEX solution for the station/ | | | | receiver coordinates which match | | | | the clock solution | | | | | | | | * REQUIRED for data types "Ax" | | | | | | +--------------------+------------------------------------------+------------+ |SOLN STA NAME / NUM | For each station/receiver included in | | | | the clock data records, as well as the | | | | analysis reference clock even if it has | | | | zero values and is not included in the | | | | data records (number given in the | | | | previous header record), include one | | | | record with the following information: | | | | - 4-character station/receiver name | A4,1X, | | | designator | | | | - Unique station/receiver identifier, | A20, | | | preferably the DOMES number for | | | | fixed stations | | | | - Geocentric XYZ station coordinates | I11,X, | | | corresponding to the analysis clock | I11,X, | | | values reported (in millimeters!) | I11 | | | | | | | * REQUIRED for data types "Ax" | | | | | | +--------------------+------------------------------------------+------------+ |# OF SOLN SATS | - Number of different satellites in the | I6,54X | | | clock data records and listed in | | | | following header records | | | | | | | | * REQUIRED for data types "AS" | | | | | | +--------------------+------------------------------------------+------------+ |PRN LIST | List of all satellites reported in this | 15(A1,I2, | | | file. Each satellite name is a | 1X) | | | 3-character string: | | | | - "Gnn" where nn is the PRN number | | | | for GPS satellites | | | | - "Rnn" where nn is the almanac number | | | | for GLONASS satellites | | | | - "Enn" where nn is the PRN number | | | | for Galileo satellites | | | | - "Cnn" where nn is the PRN number | | | | for COMPASS satellites | | | | - "Jnn" where nn is PRN-192 for the | | | | PRN number for QZSS satellites | | | | - "Snn" where nn is PRN-100 for the | | | | PRN number for SBAS payloads | | | | | | | | * REQUIRED for data types "AS" | | | | | | +--------------------+------------------------------------------+------------+ |END OF HEADER | Last record in the header section. | 60X | +--------------------+------------------------------------------+------------+ Records marked with * are optional +----------------------------------------------------------------------------+ | TABLE A16 | | CLOCK DATA FILE - DATA RECORD DESCRIPTION | +-------------+-------------------------------------------------+------------+ | OBS. RECORD | DESCRIPTION | FORMAT | +-------------+-------------------------------------------------+------------+ |TYP/EPOCH/CLK| - Clock data type (AR, AS, CR, DR, MS) | A2,1X, | | | | | | | - Receiver or satellite name | A4,1X, | | | - Receiver name is the IGS 4-character | | | | designator | | | | - Satellite name is a 3-character string: | | | | - "Gnn" where nn is the PRN number | | | | for GPS satellites | | | | - "Rnn" where nn is the almanac number | | | | for GLONASS satellites | | | | - "Enn" where nn is the PRN number | | | | for Galileo satellites | | | | - "Cnn" where nn is the PRN number | | | | for COMPASS satellites | | | | - "Jnn" where nn is PRN-192 for the | | | | PRN number for QZSS satellites | | | | - "Snn" where nn is PRN-100 for the | | | | PRN number for SBAS payloads | | | | | | | | - Epoch in specified system time (not local | | | | time!): | | | | year (4 digits),month,day,hour,min, | I4,4I3, | | | second | F10.6, | | | - Number of data values to follow | I3,3X, | | | - Clock data in the following sequence: | | | | - Clock bias (seconds) | E19.12,X | | | - Clock bias sigma [optional] (seconds) | E19.12 | +-------------+-------------------------------------------------+------------+ |TYP/EPOCH/CLK| - Clock rate [optional] (dimensionless) | E19.12,X, | | (CONT) | - Clock rate sigma [optional] (dimensionless)| E19.12,X, | | | - Clock acceleration [optional] (per second) | E19.12,X, | | | - Clock acceleration sigma [optional] | E19.12 | | | (per second) | | | | | | | | The continuation line is necessary for more | | | | than 2 data values | | | | | | | | NB: For data types "Ax", "CR", and "MS", | | | | clock data are in the sense of | | | | reported station/satellite clock | | | | *minus* reference clock value. | | | | For data type "DR", clock data are | | | | the sense of clock value after | | | | discontinuity *minus* before. | | | | | | | | Clock data apart from bias values are | | | | optional. However, if any optional values | | | | are included, then all lower order values | | | | must be supplied even if optional (although | | | | zero values may be given) | | | | | | +-------------+-------------------------------------------------+------------+ +------------------------------------------------------------------------------+ | TABLE A17 | | CLOCK DATA FILE - EXAMPLE FOR ANALYSIS DATA | +------------------------------------------------------------------------------+ ----|---1|0---|---2|0---|---3|0---|---4|0---|---5|0---|---6|0---|---7|0---|---8| 3.00 CLOCK DATA GPS RINEX VERSION / TYPE TORINEXC V9.9 USNO 19960403 001000 UTC PGM / RUN BY / DATE EXAMPLE OF A CLOCK DATA ANALYSIS FILE COMMENT IN THIS CASE ANALYSIS RESULTS FROM GPS ONLY ARE INCLUDED COMMENT No re-alignment of the clocks has been applied. COMMENT G 4 C1W L1W C2W L2W SYS / # / OBS TYPES GPS TIME SYSTEM ID 10 LEAP SECONDS G CC2NONCC p1c1bias.hist @ goby.nrl.navy.mil SYS / DCBS APPLIED G PAGES igs05.atx @ igscb.jpl.nasa.gov SYS / PCVS APPLIED 2 AS AR # / TYPES OF DATA USN USNO USING GIPSY/OASIS-II ANALYSIS CENTER 1 1994 07 14 0 0 0.000000 1994 07 14 20 59 0.000000# OF CLK REF USNO 40451S003 -.123456789012E+00 ANALYSIS CLK REF 1 1994 07 14 21 0 0.000000 1994 07 14 21 59 0.000000# OF CLK REF TIDB 50103M108 -0.123456789012E+00 ANALYSIS CLK REF 4 ITRF96 # OF SOLN STA / TRF GOLD 40405S031 1234567890 -1234567890 -1234567890SOLN STA NAME / NUM AREQ 42202M005 -1234567890 1234567890 -1234567890SOLN STA NAME / NUM TIDB 50103M108 1234567890 -1234567890 1234567890SOLN STA NAME / NUM HARK 30302M007 -1234567890 1234567890 -1234567890SOLN STA NAME / NUM USNO 40451S003 1234567890 -1234567890 -1234567890SOLN STA NAME / NUM 27 # OF SOLN SATS G01 G02 G03 G04 G05 G06 G07 G08 G09 G10 G13 G14 G15 G16 G17 PRN LIST G18 G19 G21 G22 G23 G24 G25 G26 G27 G29 G30 G31 PRN LIST END OF HEADER AR AREQ 1994 07 14 20 59 0.000000 6 -0.123456789012E+00 -0.123456789012E+01 -0.123456789012E+02 -0.123456789012E+03 -0.123456789012E+04 -0.123456789012E+05 AS G16 1994 07 14 20 59 0.000000 2 -.123456789012E+00 -.123456789012E-01 AR GOLD 1994 07 14 20 59 0.000000 4 -.123456789012E-01 -.123456789012E-02 -.123456789012E-03 -.123456789012E-04 AR HARK 1994 07 14 20 59 0.000000 2 .123456789012E+00 .123456789012E+00 AR TIDB 1994 07 14 20 59 0.000000 6 .123456789012E+00 .123456789012E+00 .123456789012E+00 .123456789012E+00 .123456789012E+00 .123456789012E+00 ----|---1|0---|---2|0---|---3|0---|---4|0---|---5|0---|---6|0---|---7|0---|---8| +------------------------------------------------------------------------------+ | TABLE A18 | | CLOCK DATA FILE - EXAMPLE FOR CALIBRATION/DISCONTINUITY DATA | +------------------------------------------------------------------------------+ ----|---1|0---|---2|0---|---3|0---|---4|0---|---5|0---|---6|0---|---7|0---|---8| 2.00 CLOCK DATA RINEX VERSION / TYPE TORINEXC V9.9 USNO 3-APR-96 00:10 PGM / RUN BY / DATE EXAMPLE OF A CLOCK DATA FILE COMMENT IN THIS CASE CALIBRATION/DISCONTINUITY DATA GIVEN COMMENT 10 LEAP SECONDS 2 CR DR # / TYPES OF DATA USNO 40451S003 STATION NAME / NUM UTC(USNO) MASTER CLOCK VIA CONTINUOUS CABLE MONITOR STATION CLK REF END OF HEADER CR USNO 1994 07 14 20 59 50.000000 2 .123456789012E+00 .123456789012E-01 CR USNO 1994 07 14 22 19 30.000000 2 -.123456789012E+00 .123456789012E-02 DR USNO 1994 07 14 22 23 14.500000 2 -.123456789012E+01 .123456789012E+00 CR USNO 1994 07 14 23 44 50.000000 2 -.123456789012E+02 .123456789012E+00 ----|---1|0---|---2|0---|---3|0---|---4|0---|---5|0---|---6|0---|---7|0---|---8|