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ITRS和WGS84
上次更新时间：2013-12-11
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一般来说，ITRS（及其实现ITRFyy）与WGS84相同
在一米的高度。
同时，有两种WGS84实现：
-基于GPS数据的WGS84的新实现，如WGS84（G730，G873，
G1150和G1674）。这些新的WGS84实现与ITRF一致
大约10厘米高。对于这些认识，没有官方的
转换参数。这意味着我们可以认为
坐标也以10厘米的WGS84表示。然而，大多数
最近的G1674实现采用了ITRF2008坐标的一半以上
其他站点的参考站和附近站点的速度。因此，
ITRF2008和WGS84（G1674）可能在厘米水平上一致，
产生传统的0变换参数。
有关WGS84实现的更多信息，请参见：
. U、 美国国家图像和地图局，“国防部世界”
大地测量系统1984——定义及其与局部大地测量的关系
系统。“NIMA技术报告8350.2第3版，密苏里州圣路易斯，6月23日
2004年。http://earth-info.nga.mil/GandG/publications/tr8350.2/tr8350_2.html
. Wong R.，C.M.Rollins和C.F.Minter（2012）WGS 84的最新更新
参考框架，第25次国际技术会议记录
导航研究所卫星部门（ION GNSS 2012），
p1164-1172页。
-基于美国海军导航卫星系统的旧实现，
通常称为多普勒经纬仪，并提供站坐标
精确到一米左右。关于这一认识
几年前，我们发布了
ITRF90和该多普勒实现系统：
ITRF90到WGS84多普勒实现系统的参数
T1 T2 T3 D R1 R2 R3型
单位-----（m）（m）（m）（ppm）（以“）”（“）（”）
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0.060-0.517-0.223-0.011 0.0183-0.0003 0.0070

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ITRS and WGS84
Last update : 2013-12-11
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In general the ITRS (and its realizations ITRFyy) are identical to WGS84 at one meter level.

Meanwhile there are two types of WGS84 realizations:

- New realizations of WGS84 based on GPS data, such as WGS84(G730, G873, G1150 and G1674). These new WGS84 realizations are coincident with ITRF at about 10-centimeter level. For these realizations there are no official transformation parameters. This means that one can consider that ITRF coordinates are also expressed in WGS84 at 10 cm level. However, the most recent G1674 realization adopted ITRF2008 coordinates for more than half of the reference stations and velocities of nearby sites for the others. Thus, ITRF2008 and WGS84(G1674) are likely to agree at the centimeter level, yielding conventional 0-transformation parameters.

For more information about WGS84 realizations, see:
. U.S. National Imagery and Mapping Agency, "Department of Defense World Geodetic System 1984 -- Its Definition and Relationships with Local Geodetic Systems." NIMA Technical Report 8350.2 3rd release, St. Louis, MO, 23 June 2004. http://earth-info.nga.mil/GandG/publications/tr8350.2/tr8350_2.html . Wong R., C. M. Rollins and C. F. Minter (2012) Recent Updates to the WGS 84 Reference Frame, Proceedings of the 25th International Technical Meeting of the Satellite Divison of the Institution of Navigation (ION GNSS 2012), p1164-1172.

- old realization based on U.S. Navy Navigation Satellite System, commonly known as DOPPLER Transit, and provided station coordinates with accuracies of about one meter. With respect to this realization we published, some years ago, transformation parameters between TRF90 and this Doppler realized system:

Parameters from ITRF90 to WGS84-Doppler realized system

T1 T2 T3 D R1 R2 R3
UNITS -----> (m) (m) (m) (ppm) (") (") (")

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0.060 -0.517 -0.223 -0.011 0.0183 -0.0003 0.0070