Date: Tue, 29 Sep 2009 10:11:55 -0400 From: "Jim.Ray" Subject: [IGSMAIL-6007]: proposed change to IGL sp3 file contents POSTPONED To: IGSMail , Canadian Space Geodesy Forum Reply-to: jim.ray@noaa.gov Message-id: <4AC215AB.2050806@noaa.gov> Content-type: text/plain; charset=ISO-8859-1; format=flowed Content-transfer-encoding: 7bit User-Agent: Thunderbird 2.0.0.23 (Windows/20090812) Sender: owner-igsmail Precedence: bulk ****************************************************************************** IGS Electronic Mail 29 Sep 07:12:08 PDT 2009 Message Number 6007 ****************************************************************************** Author: Jim Ray & Jake Griffiths Our earlier proposal to merge IGS Final SP3 files for GPS and GLONASS orbits (see message below) is postponed! Among other suggestions, it was recommended that rather than change the contents of the present IGL files, a better approach would be to create a completely new SP3 file to contain all future GNSS satellites. In trying to implement this suggestion, we realized that the satellite clock information in any merged file would be inconsistent between systems (as well as some more minor consistency problems). To comply with the SP3 standards, non-GPS clocks would have to be deleted until future improvements allow consistent estimates of all clocks relative to a common timescale. We will continue to study options for a multi-GNSS Final SP3 product that is consistent with the format specs. Meanwhile no changes will be made. -------- Original Message -------- ****************************************************************************** IGS Electronic Mail 28 May 11:23:53 PDT 2009 Message Number 5950 ****************************************************************************** Author: Jim Ray & Jake Griffiths It has been suggested that probably very few users of IGS GLONASS orbit products (file types iglWWWWD.sp3) fail to also use at the same time the associated GPS orbits for the same week WWWW and day D (files igsWWWWD.sp3). So as a convenience to users it is proposed to change the contents of the igl files to include *both* GLONASS *and* GPS orbits together. The associated igs sp3 files would not be changed in any way. We therefore plan to implement such a change starting with the release of Final products on 01 October 2009. If any igl users object to such a change or the proposed implementation date, please contact us to explain how this would present a problem for you, at: igs.acc @ noaa.gov Thanks.