[IGSMAIL-5399]: Request for Comments regarding proposed change to SP3-c documentation

[Steve Hilla]

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IGS Electronic Mail      25 Aug 07:54:31 PDT 2006      Message Number 5399
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Author: Steve Hilla

To all IGS orbit Analysis Centers, and others within the IGS community
using the SP3-c orbit format:

I am e-mailing you to request comments regarding a proposed change to
the documentation describing the SP3-c orbit format.

Recently, it was proposed to add an additional Time System Indicator
code to represent Galileo System Time.  Note that the proposed
Rinex 3.00 format already has the time system identifiers:
GPS to identify GPS time,
GLO to identify the GLONASS UTC time system, and
GAL to identify Galileo system time (which should be very close to TAI).

Currently, the SP3-c documentation only allows for codes GPS and UTC.  
So, it is proposed to modify the SP3-c specifications to now offer the
following five choices for the Time System Indicator code used on
line thirteen of the header:

GPS to identify GPS time,
GLO to identify the GLONASS UTC time system,
GAL to identify Galileo system time,
TAI to identify International Atomic Time, and
UTC to identify Coordinated Universal Time.

This is a minor change which does not affect the actual format of the
data fields, so the name of the format will remain SP3-c.  If anyone
has any comments regarding these five codes, please e-mail them to
me sometime before September 11th, 2006.


Thanks and best regards,
Steve Hilla

Steve Hilla N/NGS6
National Geodetic Survey, NOAA
1315 East-West Highway, SSMC-3
Silver Spring, Marylnad 20910
Tel.  301-713-2851
Fax. 301-713-4475
Steve.Hilla at noaa.gov