From J Wed May 1 13:41:07 1996 From: J (J) Date: Wed, 1 May 1996 13:41:07 PDT Subject: [IGSMAIL-1299] Station Report Message-ID: ****************************************************************************** IGS Electronic Mail Wed May 1 13:41:07 PDT 1996 Message Number 1299 ****************************************************************************** Author: J F Zumberge Subject: Station Report Date: May 1, 1996 To: IGS Colleagues Beginning today, as part of the Central Bureau's (CB) task to "...monitor network operations and quality assurance of data..." (IGS Terms of Reference), daily and weekly Station Reports are generated by the Satellite Geodesy and Geodynamics Systems Group at JPL for the CB. These are available at igscb.jpl.nasa.gov. For example netscape ftp://igscb.jpl.nasa.gov/igscb/mail/igsnet/weekly/1996-04-21.gz will display the report for seven days beginning April 21, 1996, and netscape ftp://igscb.jpl.nasa.gov/igscb/mail/igsnet/daily/1996-04-25.gz will display the report for the single day April 25, 1996. (Of course, regular anonymous ftp can be used to retrieve files. Once logged on to igscb.jpl.nasa.gov, cd to /igscb/mail/igsnet/daily for daily reports or /igscb/mail/igsnet/weekly for weekly reports.) Every Wednesday for the week that ended the previous Saturday, a weekly report is distributed to IGS station operators, the Governing Board, AC and AAC personnel, and Data Center personnel. The first such report was mailed earlier today. (If you want to be added to or removed from the distribution list, send your request to robliu at igscb.jpl.nasa.gov.) Documentation can be found in ftp://igscb.jpl.nasa.gov/igscb/data/network/igsnet.doc which is included below for your convenience. Sincerely, Jim Zumberge ________________________________________________________________________ 96/04/05 J F Zumberge jfz at cobra.jpl.nasa.gov This document describes the Station Report that is generated periodically for the IGS Central Bureau by JPL's Satellite Geodesy and Geodynamics System (SGGS) Group, based on Rinex data provided by the GPS Networks and Operations (GNO) Group. An example is given in Table 1. There are four numeric fields: "overall", "quantity", "quality", and "latency". Each is a floating point number, although the results are rounded to the nearest integer. The overall field is the average of the other three fields. The highest and best value for each field is 10. Before describing how these numbers are computed, we first refer to the procedure announced in IGS mail 1187, (Jan 16, 1996): Rapid precise GPS orbit and clock solutions are now available from JPL in sp3 format (see below for access details) within about 20 hours of the close of the UTC day. These rapid orbits typically agree with the final JPL IGS orbit to about 20 cm rms. Earth orientation is adjusted in these solutions and reported to the IGS, IERS, and USNO. These solutions are used to compute rapid solutions from over 100 sites daily, including all SCIGN sites in southern California. These rapid positions typically agree with our final positions at the sub-cm level. Publicly available Rinex data from new sites will be processed as the sites become operational. Results are available upon request for sites of interest. A 3-day predicted orbit is also available in the sp3 format. Because of the rapid turn-around, this means that a real-time orbit, based on extrapolations of between 20 and 44 hours, is available, with an accuracy significantly better than the broadcast orbits. We find that 24 hour predicted orbits are typically 50-80 cm, and 48 hour predictions generally 1-2 meters. The final JPL IGS orbit and Earth orientation are now computed with a 4 day lag (access details below). All sites are also processed using this final orbit, with ambiguities resolved for regional networks. One of the results of the "rapid solutions" mentioned in this excerpt is shown in Table 2. (Several of the fields in the full database from which Table 2 was extracted can be viewed graphically at http://milhouse/eng/eng.html.) There is one rapid solution for each site on each day (assuming that the Rinex file has been made available to the SGGS Group by the GNO Group). The phase and pseudorange data are used to estimate the usual receiver-specific parameters: Cartesian coordinates, receiver clock, and zenith troposphere delay. Transmitter parameters -- satellite positions and clock corrections -- are fixed at their values determined in the rapid global solution. In Table 2, the "number of time tags for which clock solution is valid" field, call it N, reflects data availability. The normal data rate analyzed is 5 minutes; there are thus 288 times in a 24-hr period for which data exists. The value of the "quantity" field is therefore quantity = /28.8, where is the average value of N over the period of interest, usually 1 week. This number can be less than 10 if either (a) one or more days of data are missing or (b) some of the data have been rejected as outliers. The quality field is also the average over one or more days of a daily quality figure. The daily quality figure is based on several categories. One quality point is awarded on each day for each of the following conditions: - there are at least 250 valid clock solutions - there are fewer than 100 phase bias resets (the last field in Table 2) - the 3d formal error of the solution for station location is less than 1 cm (this field is not in Table 2, but is in a related database) - the pseudorange rms residuals (field 8 in Table 2) are less than 86 cm (this is true 95% of the time), and the number of pseudorange measurements is at least 90% of the number of phase measurements - the phase rms residuals (field 10 in Table 2) are less than 13 mm (also true 95% of the time) Thus a site can be awarded up to 5 quality points every day. The quality field is thus quality =

/0.5, where

is the average number of points awarded over the period (again, typically a week) reported. The latency field measures the delay between the beginning of data in the file and the availability of the file, minus 1 day to account for the span of the data. A latency database is maintained for each of the three IGS Global Data Centers. The latency for a given site and day is the minimum value from the three centers. (If no centers have the data, then the latency is based on the GNO value.) Very late or missing files are assumed to have a latency of 100 hr. The latency is calculated as latency = 10 - /10, where is the average latency, in hours, over the period. [A subset of engineering data -- like shown in Table 2 -- can be made available on request. Questions/comments should be directed to me at the e-mail address listed above.] _______________________________________________________________________________ Table 1 Example of Station Report ------------------------------------------------------------------------------ _____________________________________________________________________ Station Report for 7 days beginning 1996-03-24 (generated 1996-04-05 09:38) NOTICE: The information listed below results from JPL IGS Analysis Center procedures based on Rinex data available from JPL's GPS Networks and Operations Group, and does not necessarily reflect the operational quality of any site. For all numeric fields, a 10 is the highest (and best), a 0 is the lowest. The "overall" field is the average of the quantity, quality, and latency fields. The "quantity" field indicates how much usable data from the site was available. The "quality" field accounts for amount of data, number of phase breaks, formal errors of (precise) point-positioned coordinates, and pseudorange and phase residuals. The "latency" field will be 10 for a site whose data are available, on average, within 5 hours of the end of the GPS day. It will be reduced by 1 point for each additional 10 hours of delay. (More detailed information can be found in ftp://igscb.jpl.nasa.gov/igscb/data/network/igsnet.doc.) _____________________________________________________________________ IGS Fiducial Sites site overall quantity quality latency agency location --------------------------------------------------------------------- algo 10 10 10 9 NRCan-GSD Canada fair 8 9 7 9 JPL USA gold 8 8 7 7 JPL USA hart 0 0 0 0 CNES South Africa kokb 10 10 10 10 JPL USA kosg 10 10 9 9 DUT The Netherlands madr 9 9 7 9 JPL Spain sant 9 10 8 9 JPL Chile tidb 8 8 6 9 JPL Australia trom 6 6 5 8 NMA Norway wett 8 9 7 9 IfAG Germany yar1 9 10 8 9 JPL Australia yell 9 8 9 9 NRCan-GSD Canada _____________________________________________________________________ Other IGS Global Sites site overall quantity quality latency agency location --------------------------------------------------------------------- albh 10 10 10 9 NRCan-GSC Canada ankr 8 10 10 5 IfAG Turkey areq 9 10 10 8 JPL Peru bor1 10 10 10 9 SRC-PAS Poland brmu 9 9 9 10 NOAA USA brus 10 10 10 9 ROB Belgium cas1 8 9 9 7 AUSLIG Antarctica chat 7 7 7 6 JPL New Zealand fort 9 10 9 8 NOAA Brazil guam 9 10 10 8 JPL Guam hob2 0 0 0 0 AUSLIG Australia iisc 9 9 8 9 JPL India irkt 8 9 9 5 DUT Russia kely 4 2 3 5 NOAA Greenland kerg 9 10 8 9 CNES Kerguelen Islands kiru 10 10 9 10 ESA Sweden kit3 6 7 7 5 GFZ Uzbekistan kour 8 9 6 10 ESA French Guiana lpgs 5 5 5 5 GFZ Argentina mac1 4 4 4 4 AUSLIG Australia mali 7 8 5 9 ESA Kenya mas1 4 3 2 7 ESA Spain mate 7 7 5 8 ASI Italy mcm4 10 10 10 9 JPL Antarctica mdo1 9 9 10 7 JPL USA mdvo 8 8 8 7 DUT Russia mets 7 6 6 8 FGI Finland nlib 10 10 10 9 JPL USA ohig 6 7 7 4 IfAG Antarctica onsa 8 7 7 9 OSO Sweden pama 7 8 5 8 CNES Tahiti pert 9 9 9 10 ESA Australia pie1 10 10 10 9 JPL USA pots 8 9 7 10 GFZ Germany rcm5 9 9 8 10 NOAA USA sey1 0 0 0 0 JPL Seychelles shao 9 10 8 8 JPL China stjo 10 10 10 9 NRCan-GSD Canada taiw 8 9 7 10 IES-AS Taiwan thu1 9 9 9 9 JPL Greenland tskb 10 10 10 9 GSI Japan usud 10 10 10 9 JPL Japan vill 10 10 10 10 ESA Spain zwen 6 6 5 7 GFZ Russia _____________________________________________________________________ Other IGS Sites (retrieved by JPL) site overall quantity quality latency agency location --------------------------------------------------------------------- aoa1 10 10 10 9 JPL USA auck 8 9 9 7 JPL New Zealand blyt 10 10 10 9 SIO USA bogt 9 9 9 9 JPL Columbia bran 5 6 5 4 USGS-SIO USA braz 0 0 0 0 IBGE-JPL Brazil carr 10 10 10 9 JPL USA casa 9 9 7 9 JPL USA cat1 10 10 10 9 JPL USA chil 8 9 9 6 USGS-SIO USA cit1 10 10 10 9 JPL USA coso 9 9 9 10 SIO USA crfp 9 9 9 9 SIO USA cro1 10 10 10 9 NRAO-JPL US Virgin Islands dav1 5 4 4 5 AUSLIG Antarctica drao 10 10 10 9 NRCan-GSC Canada ebre 2 3 3 1 ICC Spain eisl 9 10 9 9 JPL Chile gode 10 10 10 9 NASA-GSFC USA gope 9 9 9 8 RIG Czech Republic gras 9 10 10 7 CNES France graz 8 8 7 9 ISR Austria harv 10 10 10 9 JPL USA hers 8 9 7 8 RGO United Kingdom holc 8 10 10 4 USGS-SIO USA joze 9 10 10 8 IGGA-WUT Poland jplm 10 10 10 9 JPL USA lama 0 0 0 0 OUAT Poland lbch 10 10 10 9 JPL USA lhas 0 0 0 0 IfAG China long 5 6 4 5 USGS-SIO USA math 7 10 10 0 SIO USA monp 8 7 8 9 SIO USA noto 8 10 10 5 ASI Italy nyal 8 8 7 8 NMA Norway oat2 10 10 10 9 JPL USA pin1 8 9 9 8 SIO USA pol2 7 7 7 7 UNAVCO Kyrgyzstan pvep 9 10 7 9 SIO USA quin 10 10 10 9 JPL USA reyk 6 4 4 9 IfAG Iceland sio3 10 10 10 9 SIO USA sni1 0 0 0 0 JPL USA spk1 10 10 10 9 JPL USA taej 8 6 7 10 KAO Korea trak 8 9 7 8 SIO USA uclp 10 10 10 9 JPL USA upad 6 7 7 5 UP Italy usc1 10 10 10 9 JPL USA vndp 9 9 10 9 SIO-JPL USA wes2 9 9 10 10 NOAA USA whc1 9 10 10 9 JPL USA whi1 9 10 9 9 JPL USA wlsn 10 10 10 9 JPL USA wtzr 10 10 10 9 IfAG Germany zimm 9 9 8 9 FOT Switzerland _____________________________________________________________________ Other IGS Sites (not retrieved by JPL) site agency location --------------------------------------------------------------------- cagl ASI Italy hflk ISR Austria medi ASI Italy roch SIO USA sfer ROA Spain _____________________________________________________________________ Other Sites (no log file at IGS CB) site overall quantity quality latency agency location --------------------------------------------------------------------- brib. 9 10 9 9 USGS USA chab. 7 10 9 3 USGS USA cice. 10 10 10 9 JPL Mexico clar. 8 10 8 6 USGS USA cmbb. 0 0 0 0 USGS USA cmp9. 8 10 10 6 USGS USA dam1. 7 8 9 3 USGS USA dam2. 5 4 4 6 USGS USA denc. 0 0 0 0 CORS USA fai2. 10 10 10 9 JPL USA farb. 9 10 10 7 USGS USA gol2. 10 10 10 9 JPL USA hbrk. 3 0 0 10 CORS USA hklo. 3 0 0 10 CORS USA holp. 8 10 10 6 USGS USA hopb. 6 4 4 9 USGS USA krak. 3 0 0 8 JPL USA leep. 8 10 10 5 USGS USA lmno. 3 0 0 10 CORS USA moin. 3 0 0 9 JPL Costa Rica mola. 8 10 10 4 USGS USA nune. 8 10 10 4 USGS USA pltc. 3 0 0 10 CORS USA rock. 8 10 10 5 USGS USA sol1. 9 9 9 9 NOAA/NASA USA strl. 3 0 0 9 CORS USA tabl. 4 3 3 5 USGS USA tibb. 6 4 4 9 USGS USA tid2. 10 10 10 9 JPL Australia tmgo. 8 7 7 9 CORS USA usna. 9 9 9 9 NOAA/NASA USA vcio. 3 0 0 10 CORS USA wint. 8 10 10 3 USGS USA wlps. 3 0 0 9 CORS USA wsmn. 3 0 0 10 CORS USA _____________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ Table 2 Engineering data for precise-point-positioned sites ------------------------------------------------------------------------------- date | site | | number of time tags for which clock solution is valid | | | rms deviation from straight line of clock solution (ns) | | | | drift of clock solution (parts per trillion) | | | | | clock solution at noon (usec) | | | | | | # of pseudorange meas. | | | | | | | rms (cm) | | | | | | | | # of phase meas. | | | | | | | | | rms (mm) | | | | | | | | | | orig | | | | | | | | | | | tot | | | | | | | | | | <-breaks-> |________ |___ |_ |_______ |_______ |_______ |___ |_ |___ |_ |_ |_ ... 1996-02-25 IISC 288 69.9 0.247 -0.00443 1677 70 1675 13 69 69 1996-02-25 IRKT 287 147 9.47 -0.214 1650 46 1650 8 51 51 1996-02-25 JOZE 286 36.2 -94.8 181 1653 50 1653 7 39 39 1996-02-25 JPLM 288 41.7 114 1.4e+03 1667 26 1667 6 44 47 1996-02-25 KERG 288 70.9 7.06 -660 0 . 1552 5 53 53 1996-02-25 KIRU 288 3.08 -0.00867 11.7 1427 50 1427 10 67 80 1996-02-25 KIT3 288 126 0.0974 -0.0181 1642 66 1642 11 47 47 1996-02-25 KOKB 288 0.131 0.366 0.00596 1661 55 1661 6 45 50 1996-02-25 KOSG 288 1.02 -3.94 20.5 1324 38 1324 5 44 44 ... _______________________________________________________________________________ 96/04/05 /users/igscb/work/data/network/SCCS/s.igsnet.doc [Mailed From: jfz at cobra.jpl.nasa.gov]