Delivered-To: igsmail@igscb.jpl.nasa.gov Date: Fri, 20 May 2005 16:39:35 +0200 From: Stefan Schaer Subject: [IGSMAIL-5151]: GLONASS MW antenna offset values To: igsmail Message-id: <428DF6A7.6040901@aiub.unibe.ch> Organization: Astronomical Institute, University of Berne Content-type: text/plain; charset=us-ascii; format=flowed Content-transfer-encoding: 7bit User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.4) Gecko/20030624 Netscape/7.1 (ax) Sender: owner-igsmail Precedence: bulk ****************************************************************************** IGS Electronic Mail 20 May 07:39:40 PDT 2005 Message Number 5151 ****************************************************************************** Author: Stefan Schaer Dear IGLOS colleagues, The X-component of the GLONASS-M MW antenna offset vector is, with nominally -0.545 m, remarkably big. See also: http://igscb.jpl.nasa.gov/mail/igsmail/2005/msg00027.html Note that the axis notation used for GLONASS SVs differs from that used for GPS (specifically Y_GLONASS corresponds to -X_GPS). The mentioned X-offset value could be verified on the basis of CODE GNSS analysis results. Furthermore, our test computations showed that disregarding the nominal GLONASS Z-offset value (of 1.620 and 2.183 m, respectively) is still advisable (at least when relying on "relative" receiver antenna PCV calibration models). Also, comparisons with SLR range measurements to GLONASS SVs indicated that this is an adequate approach. Starting with GPS week 1321, BKG, ESA, and CODE will start to refer their GLONASS orbit products to the following satellite antenna offset (SAO) values: X/Y/Z = 0.000/0.000/0.000 m for GLONASS and X/Y/Z = -0.545/0.000/0.000 m for GLONASS-M SVs. The SAO values specified above may be considered "recommended to be adopted for use with IGS/IGLOS GNSS/GLONASS orbit products" (until the expected change to "absolute" GPS/GLONASS SAO and SAP calibration models). Best regards, The CODE AC Team