Amsterdam

AMSA 91401S001

AMSB 91401S002

AMTB 91401S003

AMUB 91401S004

AMVB 91401S005

JoG AMSA antenna movement from 01-JAN-1996 to 21-APR-1997 (end). Data should be deleted during this period

IDS AMSA antenna movement from 01-JAN-1996 to 21-APR-1997 (end). Data should be deleted during this period

JoG AMSB antenna movement. No data at all should be used for AMSB

IDS AMSB antenna movement. No data at all should be used for AMSB

ITRF: AMSB is not in ITRF2005

SIMB: AMSB = AMTB, as local tie is

AMTB 91401S003 AMSB 91401S002 0.000 0.000 0.000 0.001

IGN/SIMB mentioned a centering problem for AMTB in DORISMAIL#497 on 24-NOV-2005. We then add a discontinuity in the time series. However, as the difference is about 5 mm, we chose to use the exact same coordinates for the time being.

AMVB is not in ITRF2005. See DORISMail #0598

Preliminary computations:

Use AMTB position/velocity in ITRF2005

AMTB 2000.0 1086063.011 4927948.514 -3887839.993 -10.91 3.87 -3.06

However, here is the AMTB position/velocity in ITRF2005 from my own DORIS solution, without using the geodetic local tie information, just assuming that AMSA and AMTB have the same velocity:

(from ign07d02)

AMTB 1086063.025 4927948.502 -3887839.991 -14.67 7.02 -1.48

The position seems OK and the velocity is close

Using more recent DORIS solution (ign07d02) expressed in ITRF2005 and fixing velocity to the above ITRF2005 values, we obtain :

2000.0 AMTB 1086063.0064 4927948.5182 -3887839.9851 -10.91 3.87 -3.06

statistics AMTB XYZ 0.0013 0.0011 0.0010 254

so it is in good agreement with ITRF2005

To estimate AMUB coordinates, we can use the following geodetic local tie

AMUB 91401S004 AMTB 91401S003 -0.026 -0.117 0.093 0.001

We then obtain:

AMUB 2000.0 1086063.037 4927948.631 -3887840.086 -10.91 3.87 -3.06

Using more recent DORIS solution (ign07d02) expressed in ITRF2005 and fixing velocity to the above ITRF2005 values, we obtain :

2000.0 AMUB 1086063.0265 4927948.6318 -3887840.0705 -10.91 3.87 -3.06

statistics AMUB XYZ 0.0031 0.0020 0.0015 34

so this is good agreement

For AMVB, using most recent DORIS data (ignwd08), we obtain

2000.0 AMVB 1086063.0851 4927948.7551 -3887840.1944 -10.91 3.87 -3.06

statistics AMVB XYZ 0.0030 0.0022 0.0022 31

While the a priori position in the DORISMail is

X = 1086063.069 m Y = 4927948.776 m Z = -3887840.197 m

(sigma: 2 mm for each component)

The ITRF2005 velocities for this site are:

VX = -0.0109 m/y VY = 0.0039 m/y VZ = -0.0031 m/y

SigVX = 0.0005 m/y SigVY = 0.0004 m/y SigVZ = 0.0004 m/y

Which is in good agreement

Recommendation:

AMSA data should be deleted from 01-JAN-1996 to 21-APR-1997

Use AMTB from ITRF2005

Put a discontinuity for AMTB on 24-NOV-2005 (following DORISMAIL#497)

Derive AMUB from AMTB value

AMUB 2000.0 1086063.037 4927948.631 -3887840.086 -10.91 3.87 -3.06

For AMVB, use the most recent DORIS data

2000.0 AMVB 1086063.0851 4927948.7551 -3887840.1944 -10.91 3.87 -3.06

statistics AMVB XYZ 0.0030 0.0022 0.0022 31