From stefan.schaer at aiub.unibe.ch Wed Jul 30 07:53:59 2003 From: stefan.schaer at aiub.unibe.ch (Stefan Schaer) Date: Wed, 30 Jul 2003 16:53:59 +0200 Subject: [IGSMAIL-4530]: CODE ultra rapid GNSS orbits Message-ID: <3F27DC07.B4B69537@aiub.unibe.ch> ****************************************************************************** IGS Electronic Mail 30 Jul 07:54:02 PDT 2003 Message Number 4530 ****************************************************************************** Author: Stefan Schaer Dear colleagues, Until recently, the CODE, or COU ultra rapid orbits/ERPs were directly derived from our rapid products. These results were actually pure predictions and were therefore treated in the IGU combination just for comparison purposes (although the previous IGU combined SP3 orbit files indicated COU as contributing analysis center). The current COU orbit/ERP products are now real (i.e., supported by hourly observation data). As a matter of fact, our ultra rapid products are GNSS products, since we do not only consider GPS but also GPS/GLONASS-mixed hourly observation data in our ultra rapid analysis. It should be mentioned that the IGLOS data volume with respect to hourly data is (still) very limited (DWH1, UNB1, plus many European stations). Anyway, the quality of COU GLONASS orbits is already significantly better than that of broadcast information. We hope that other IGLOS stations (in particular all remote IGLOS stations!) are encouraged to supply hourly observation data. Those of you interested in the quality assessment of COU GPS orbits are referred to the most recent igu-cmp-sum (comparison) files and future igu-sum (combination) files stored at ftp://cddisa.gsfc.nasa.gov/pub/gps/products/ or made available by the IGS ACC at ftp://ftp.gfz-potsdam.de/pub/pub/igsacc/product/ultra/ COU products should be considered for the first time in today's 15-UT IGU combination. Many thanks to Gerd Gendt for the adaptations in this regard. Best regards, Stefan