From Geodetic Tue Jan 4 07:17:58 1994 From: Geodetic (Geodetic) Date: Tue, 4 Jan 1994 7:17:58 PST Subject: [IGSREPORT-0687] EMR Analysis Report (w. 729) Message-ID: ****************************************************************************** IGS Electronic Report Tue Jan 4 7:17:58 PST 1994 Message Number 0687 ****************************************************************************** Author: Geodetic Survey of Canada Subject: EMR Analysis Report (w. 729) (Dec 26 - Jan 01,94) Our analysis utilizes the JPL GIPSY/OASIS II (UNIX) software system and data from all (up to 7) Canadian stations augmented by up to 12, globally distributed, core stations (see Table 1 for the list of stations). This effort is a part of a joint pilot project called "Active Control System" and involves the Geodetic Survey Division (GSD), SMRSS; the Geophysics Division and Pacific Geoscience Centre of the Geological Survey of Canada, all three institutions are part of the Department of Natural Resources (NRCan), (formerly the Department of Energy, Mines & Resources (EMR)). Table 1 : Station Summary (also indicated are day no. for which a particular station is not included in the daily solution, either due to being down or data being late). STATION IGS code MISSING DAY NO. 1993 Albert Head, CAN ALBH Algonquin, CAN ALGO* Fairbanks FAIR* Goldstone GOLD* Hartebeesthoek HART* Holberg,CAN HOLB Kokee Park KOKB Madrid MADR* McMurdo MCMU 360 to 001 Pamatai PAMA 365 Penticton, CAN DRAO Santiago SANT* St. Johns, CAN STJO Canbera TIDB* Tromsoe TROM* 364, 365 Wettzell WETT* Yarragadee YAR1* Yellowknife, CAN YELL* * indicates constrained stations, remaining are solved for (50m apriori sig.) SOLUTION CHARACTERISTICS Reference frame and orientation: Nominally ITRF91, at epoch 1992.5 is realized by constraining up to 12 of the above stations at the IGS coordinates (see IGS message #90). Orientation is realized through the above coordinates and, once a week, the fixed DUT1 values from the current NEOS/IERS (Bull. A). Constants and models: - no change, see the IGS mess. #101 for details. Estimation strategies: - no change, see the IGS mess. #101 for details - , except for the estimation of DUT1, stochastic orbit modeling, new weighting of L3,P3, see IGS mess. #130. ALGO was used as time reference. Aposteriori variance factors typically are between 0.5 and 1.0 (noise about 3mm and 200mm for phase and smoothed pseudorange observations, resp.). PRODUCTS GENERATED: The following products are generated and uploaded into CDDIS @ NASA/GSFC EMR07290-6.SP3 GPS ephem. files for days 0-6, week #729 in sp3 format EMR07297.ERP pole x,y and DUT1 solutions for week #729 EMR07297.SUM name of this text summary file REMARKS on EMR's products: 1. ALGO hydrogen maser used as a time reference. In the sp3 EPH file sat. epochs with no reference (e.g. ALGO not observing a satellite) have a value of 99999. microseconds. ALGO clock error & drift were about -1900 ns (49347) & -20 ns/day w.r.t. GPS time. 2. Starting with the week #720 we are assigning nominal sigma codes of 8(256mm) for all the orbits passing our quality analysis. For errors larger than 1.5m we are assigning sigmas of abs(error)/4, expressed by the binary exponent in the sp3 header. 3. Starting with the week #726, the name of the ephemeris file will end with ".sp3" instead of ".eph".