[IGSMAIL-5401]: revisions to clock RINEX format

[Jim Ray "(NGS" 301-713-2850 "x112)" <jimr @ ngs.noaa.gov>]

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IGS Electronic Mail      30 Aug 11:51:00 PDT 2006      Message Number 5401
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Author: Jim Ray

It has been suggested that changes are needed in the clock RINEX format
(last updated 16 June 19999) to be consistent with RINEX version 3.00 and
to recognize the use of other Global Navigation Satellite Systems (GNSSs)
besides the Global Positioning System (GPS).  Proposed changes so far
include:

  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 Space-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 "SAT ANT PCO / PCV" 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.
     [NOTE: The format -- taken from RINEX 3.00 is not adequate to give
      DCBs for each satellite.  Further changes are under discussion.]
  h. Capability of handling inter-system timing biases (possibly as a new
     type of CR data record) are under consideration.

To view the pending revised version, please see:
  ftp://www.ngs.noaa.gov/dist/jimr/rinex_clock.30aug06

Send any comments to me and Werner Gurtner (werner.gurtner @ aiub.unibe.ch).
Thanks,
--Jim