ITRF (International Terrestrial Reference Frames)
ITRF2020(全英语，有点费力）
http://www.gnsser.com/Information/ViewDetails/377
IGS参考框架年表的使用
2018-5-4 21:35:43来源: Gnsser 译自 IGS 发布人: czsgeo
IGS参考框架年表的使用
IGS不时更改用于表达其产品的地面参照系，通常涉及国际地面参照系（ITRF）的更新。 下面列出了IGS变化的年代表。
ITRF92
1994-01-02至1994-12-31
从0730到0781GPS周
多达13个参考站与SLR和/或VLBI共存
ITRF93
1995-01-01至1996-06-29
从0782到0859 GPS周
ITRF93相对于较早和较晚的ITRF而言是人为旋转的，因此全球无网络旋转条件没有被遵守
多达13个参考站与SLR和/或VLBI共存
ITRF94
1996-06-30至1998-02-28
GPS从0860到0946
ITRF94数据重置以强制执行全局无净旋转条件
多达13个参考站与SLR和/或VLBI共存
ITRF96
1998-03-01至1999-07-31
GPS通过0947到1020
ITRF94基准保留
多达47个参考站
见Kouba et al。（1998）
ITRF97
1999-08-01至2000-02-26
GPS周1020至1050
ITRF94基准保留
多达51个参考站
请参阅IGS Mail＃2432
ITRF97具有一致的轨道旋转对齐
2000-02-27至2000-06-03
GPS周1051至1064
ITRF94基准保留
多达51个参考站
Kouba等（1998）的准严密组合方法。 在IGS Final产品中实施
请参阅IGS邮件＃2740，＃2750和＃2751
IGS97
2000-06-04至2001-12-01
GPS周1065至1142
与ITRF97（因此ITRF94）数据对齐
多达51个参考站
请参阅IGS Mail＃2899
IGS00
2001-12-02至2004-01-10
GPS周1143至1252
与ITRF2000数据对齐，从以前的实现中更新
多达54个参考站
请参阅IGS Mail＃3605
IGb00
2004-01-11至2006-11-04
GPS从1253通过1399
与ITRF2000数据对齐，从以前的实现中更新
多达99个参考站
请参阅IGS邮件＃4642，＃4643，＃4652，＃4666和＃4748
直到在此帧期间，只有相对天线相位校准适用于地面站，并且没有用于卫星天线的校准;请参阅IGS Mail＃5189
IGS05
2006-11-05 thru 2011-04-16
GPS从1400到1631
与从ITRF2000更新的ITRF2005数据对齐
多达132个参考站
请参阅IGS邮件＃5447，＃5455和＃5438
从这一帧开始，绝对天线相位校准适用于地面站和卫星天线;请参阅IGS Mail＃5189
这个框架也被用于IGS第一次后处理活动，其产品可以返回到1994年，如IGS Mail＃6136中所述
IGS08
2011-04-17至2012-10-06
GPS从1632年到1708年
与ITRF2008数据对齐
多达232个参考站，其中多达91个被指定为IGS08“核心网”
请参阅IGS Mail＃6354
绝对天线相位校准（对于地面站和卫星天线）都改为ig08.atx; 请参阅IGS邮件＃6355和＃6374
ftp://igs.org/pub/station/coord/上的重要文件：
- IGS08.snx
- IGS08_core.txt
- ITRF2008_to_IGS08.txt
- new_calib / lat_models.txt
- perl脚本应用天线和纬度相关的天线校正，以确保igs05.atx结果与ig08.atx一致
IGb08
2012-10-07到现在
GPS通过现在1709
与ITRF2008数据对齐
IGS08的更新，主要用于恢复不可用的射频和核心站点
请参阅IGS Mail＃6663
伴随着天线校准的更新，包括IIF Block II卫星的新估计
请参阅IGS Mail＃6662
这个框架也将用于IGS第二次后处理活动
原文链接：
http://acc.igs.org/igs-frames.html
ITRF2020
ITRF2020
The ITRF2020 solution provides the usual/classicalestimates: station positions at a given epoch, station velocities and EOPs, butalso Post-Seismic Deformation (PSD) parametric models for stations subject tomajor earthquakes, as well as annual and semi-annual periodic terms expressedin the Center of Mass (CM – as sensed by SLR) frame, as well as in the Centerof Figure (CF) frame.
https://itrf.ign.fr/en/solutions/itrf2020/description/more
转换参数（ITRF2020-->ITRFxx)
( http://itrf.ensg.ign.fr/ITRF_solutions/2014/ )
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ITRF solutions available here consist in sets of station positions and velocities with their variance/covariance matrices. Recently with the release of the ITRF2005 , Earth Orientation Parameters (EOPs) have simultaneously been combined with station coordinates. The numbers (yy) following the designation “ITRF” specify the last year when data was used during frame processing. For more details, please see part 4 of the IERS technical note n°32.
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ITRF2014
Description
ITRF2014 is the new realization of the International Terrestrial Reference System. Following the procedure already used for the ITRF2005 and ITRF2008 formation, the ITRF2014 uses as input data time series of station positions and Earth Orientation Parameters (EOPs) provided by the Technique Centers of the four space geodetic techniques (VLBI, SLR, GNSS and DORIS). Based on completely reprocessed solutions of the four techniques, the ITRF2014 is expected to be an improved solution compared to ITF2008.
Two innovations were introduced in the ITRF2014 processing, namely:
Annual and semi-annual terms were estimated for stations with sufficient time-spans of the 4 techniques during the stacking processes of the corresponding time series;
Post-Seismic Deformation (PSD) models were determined by fitting GNSS/GPS data at major GNSS/GPS Earthquake sites. The PSD models were then applied to the 3 other techniques at EQ Co-location sites.
While the ITRF2014 solution provides the usual/classical estimates: station positions at a given epoch (2010.0), station velocities and EOPs, the PSD models are part of the ITRF2014 products.
