Subject: [SIR-Mail] No.619: igs08_1734.atx: Update without "spikes" in GLONASS calibrations From: Laura Sanchez ******************************************************************************** SIR Electronic Mail 2013-04-08 07:21:46 UTC Message No. 619 ******************************************************************************** Dear IGS colleagues! The absolute IGS antenna correction file (igs08_wwww.atx) has been updated. The new release is called ´igs08_1734.atx´. The phase center variations (PCVs) for the GLONASS frequencies of the following 46 antenna types were resubmitted by Geo++ GmbH: ASH700936C_M NONE ASH700936D_M SNOW ASH700936E NONE JAV_GRANT-G3T NONE JAV_RINGANT_G3T NONE JAVRINGANT_DM NONE JAVRINGANT_DM JVDM LEIAR10 NONE LEIAR25 NONE LEIAR25 LEIT LEIAR25.R3 NONE LEIAR25.R4 NONE LEIAR25.R4 LEIT LEIAR25.R4 SCIT LEIAS05 NONE LEIAS10 NONE LEIAT504GG NONE LEIATX1230+GNSS NONE LEIAX1202GG NONE LEIAX1203+GNSS NONE LEIGG02PLUS NONE LEIGS08 NONE LEIGS09 NONE LEIGS12 NONE LEIMNA950GG NONE NAX3G+C NONE NOV702GG NONE NOV750.R4 NONE RNG80971.00 NONE SEPCHOKE_MC NONE SEPCHOKE_MC SPKE STXS9SA7224V3.0 NONE TPSCR.G3 NONE TPSCR.G3 SCIS TPSCR3_GGD CONE TPSPG_A1+GP NONE TRM39105.00 NONE TRM55971.00 NONE TRM57970.00 NONE TRM57971.00 NONE TRM59800.00 NONE TRM59800.00 SCIT TRM59800.80 NONE TRM59800.80 SCIT TRMR8_GNSS NONE TRMR8_GNSS3 NONE From those phase center corrections erroneous spikes contained in the GLONASS PCVs were removed that were caused by a software bug in the format conversion from the Geo++ to the ANTEX format that was detected and corrected in November 2011. GLONASS PCVs in the ANTEX format provided by Geo++ prior to that date may be affected by spikes. Those GLONASS spikes are generally small, but could amount to several mm. As regards the antenna types contained in igs08.atx, the spikes were always smaller than 3 mm. Among the 46 affected antenna types are 37 ”original” phase center calibrations as well as 9 copied sets of corrections. The 37 original calibrations contained 281 spikes altogether. However, only 22 of them exceeded the 1 mm level: 3.0 mm <= spike 0 2.0 mm <= spike < 3.0 mm 8 1.0 mm <= spike < 2.0 mm 14 0.5 mm <= spike < 1.0 mm 38 0.2 mm <= spike < 0.5 mm 53 0.0 mm < spike < 0.2 mm 168 More information can be found at the Geo++ website: http://www.geopp.de/index.php?sprachauswahl=en&bereich=2&kategorie=3&artikel=221 An online tool allows to visualize and check the GLONASS PCVs contained in ANTEX files for the existence of spikes. Details are given on the website. The updated antenna correction model is available at ftp://igs.org/pub/station/general/igs08_1734.atx or ftp://igs.org/pub/station/general/igs08.atx As the magnitude of the spikes is small and as the induced PCV errors are isolated, the correction of the spikes should not have a systematic impact on IGS products based on GLONASS PCVs. Nonetheless, we apologize for any inconvenience this update may cause! With best regards, Ralf Schmid, Martin Schmitz and Robert Khachikyan on behalf of the IGS Antenna Working Group _______________________________________________ IGSMail mailing list IGSMail@igscb.jpl.nasa.gov http://igscb.jpl.nasa.gov/mailman/listinfo/igsmail -- Laura Sánchez Deutsches Geodätisches Forschungsinstitut Alfons-Goppel-Str. 11, 80539 München phone: +49 89 23031-1295 fax: +49 89 23031-1240 mailto:sanchez@dgfi.badw.de http://www.dgfi.badw.de/ ********************************************************************************