Chronology of IGS Reference Frame Usage
From time to time, the IGS has changed the terrestrial reference frame
that is used to express its products, usually related to updates of
the International Terrestrial Reference
Frame (ITRF). The chronology of the IGS changes is tabulated
below.
ITRF92
- 1994-01-02 thru 1994-12-31
- GPS wks 0730 thru 0781
- up to 13 reference stations colocated
with SLR and/or VLBI
ITRF93
- 1995-01-01 thru 1996-06-29
- GPS wks 0782 thru 0859
- ITRF93 was artificially rotated
with respect to earlier and later ITRFs so that the global
no-net-rotation condition was not respected
- up to 13 reference stations colocated
with SLR and/or VLBI
ITRF94
- 1996-06-30 thru 1998-02-28
- GPS wks 0860 thru 0946
- ITRF94 datum reset to enforce global
no-net-rotation condition
- up to 13 reference stations colocated
with SLR and/or VLBI
ITRF96
- 1998-03-01 thru 1999-07-31
- GPS wks 0947 thru 1020
- ITRF94 datum retained
- up to 47 reference stations
- see Kouba et al. (1998)
ITRF97
- 1999-08-01 thru 2000-02-26
- GPS wks 1020 thru 1050
- ITRF94 datum retained
- up to 51 reference stations
- see IGS Mail #2432
ITRF97 with consistent orbit rotational alignment
- 2000-02-27 thru 2000-06-03
- GPS wks 1051 thru 1064
- ITRF94 datum retained
- up to 51 reference stations
- quasi-rigorous combination methodology
of Kouba
et al. (1998) implemented in IGS Final products
- see IGS Mails #2740,
#2750, and
#2751
IGS97
- 2000-06-04 thru 2001-12-01
- GPS wks 1065 thru 1142
- aligned to ITRF97 (and hence ITRF94)
datum
- up to 51 reference stations
- see IGS Mail #2899
IGS00
- 2001-12-02 thru 2004-01-10
- GPS wks 1143 thru 1252
- aligned to ITRF2000 datum, which was
updated from prior realizations
- up to 54 reference stations
- see IGS Mail #3605
IGb00
- 2004-01-11 thru 2006-11-04
- GPS wks 1253 thru 1399
- aligned to ITRF2000 datum, which was
updated from prior realizations
- up to 99 reference stations
- see IGS Mails #4642,
#4643,
#4652,
#4666, and
#4748
- until and during this frame only
relative antenna phase calibrations were applied for ground stations
and no calibrations used for satellite antennas; see IGS Mail #5189
IGS05
- 2006-11-05 thru 2011-04-16
- GPS wks 1400 thru 1631
- aligned to ITRF2005 datum, which was
updated from ITRF2000
- up to 132 reference stations
- see IGS Mails #5447,
#5455, and
#5438
- starting with this frame absolute
antenna phase calibrations were applied both for ground stations
and satellite antennas; see IGS Mail #5189
- this frame was also used for the
IGS 1st reprocessing campaign, the
products of which are available back to 1994 as described in
IGS Mail #6136
IGS08
- 2011-04-17 thru 2012-10-06
- GPS wks 1632 thru 1708
- aligned to ITRF2008 datum
- up to 232 reference stations, of which
up to 91 have been designated as the IGS08 "core network"
- see IGS Mail #6354
- absolute antenna phase calibrations
(for both ground stations and satellite antennas) changed to
igs08.atx; see
IGS Mails #6355, and
#6374
- important files at ftp://igs.org/pub/station/coord/:
IGb08
- 2012-10-07 thru 2017-01-28
- GPS wks 1709 thru 1933
- aligned to ITRF2008 datum
- an update to IGS08, designed mostly to recover unuseable RF and core sites
- see IGS Mail #6663
- accompanied by an update to antenna calibrations, including new estimates for Block IIF satellites
- see IGS Mail #6662
- this frame will also be used for the
IGS 2nd reprocessing campaign
IGS14
- 2017-01-29 thru present
- GPS wks 1934 thru present
- aligned to ITRF2014 datum
- up to 252 reference stations as the IGS14 "core network"
- see IGS MAIL #7399
04 October 2012, originator IGS ACC