1. Reference Frame Working Group Report
AGU, S.F., Dec 10-14, 2007
Reference Frame Working Group Report
Rémi Ferland
Mike Piraszewski
Geodetic Survey Division

2. Contents Contributors Network Products Summary
IGS08, Miami, June 2-6, 2008
Contents
Contributors
Network
Reference Frame Realization Status (IGS05)
Weekly solutions (1400 – Now)
Products
Coordinates
ERP’s
Apparent Geocenter
Summary

3. Contributors Analysis Centers (ACs):
IGS08, Miami, June 2-6, 2008
Contributors
Analysis Centers (ACs):
cod Center for Orbit Determination in Europe, AIUB, Switzerland,
emr Natural Resources Canada, Canada,
esa European Space Operations Center, ESA, Germany,
gfz GeoForschungsZentrum, Germany,
jpl Jet Propulsion Laboratory, USA,
MIT Massachusetts Institute of Technology, USA,
ngs National Oceanic and Atmospheric Administration / NGS, USA,
sio Scripps Institution of Oceanography, USA,
grg (new) Groupe de Recherche en Geodesie Spatiale /CNES, France
Global Network Associate Analysis Centers (GNAACs):
mit Massachusetts Institute of Technology, USA,
ncl University of Newcastle-upon-Tyne, U.K.

4. IGS05 Reference Frame Realization (132 Stations)
IGS08, Miami, June 2-6, 2008
IGS05 Reference Frame Realization (132 Stations)
Criterions:
Geometry
Monumentation
Collocation
Performance
Data availability
Time series
Historical

5. Evolution of the Number of IGS05 Stations Processed
IGS08, Miami, June 2-6, 2008
Evolution of the Number of IGS05 Stations Processed

6. IGS05 Status Initially 132 stations (Wk 1400 – 06/11/05)
IGS08, Miami, June 2-6, 2008
IGS05 Status
Initially 132 stations (Wk 1400 – 06/11/05)
Recently ~100 stations + ~6 intermittent
Inactive ~26 … Main Causes:
Discontinuities (15)
Equipment (13)
Earthquakes (2)
Dormant (6)
Not operational (3)
IGS05 poor velocity (1)
Poor data (1)

7. IGS05 Inactive Stations (26)
IGS08, Miami, June 2-6, 2008
IGS05 Inactive Stations (26)

8. Evolution of the Number of IGS Stations Processed
IGS08, Miami, June 2-6, 2008

9. Stations in Recent IGS Weekly Solutions
IGS08, Miami, June 2-6, 2008
Stations in Recent IGS Weekly Solutions
Up to ~350 Stations

10. ACs Coordinates Residuals Avg. & Std. w.r.t. IGS05
IGS08, Miami, June 2-6, 2008 N
Consistency:
N&E ~ 3mm
H ~ 9mm
Avg. (mm)
Std. (mm) E H
Scale=3x

11. ACs Coordinates Residuals Avg. & Std. w.r.t. IGS Weekly
IGS08, Miami, June 2-6, 2008 N
Consistency:
N&E ~ 1-2mm
H ~ 3-4mm
Avg. (mm)
Std. (mm) E
jpl: switch to Absolute
Antenna phase center H
Scale=3x
esa: new software

12. ACs Coordinates Residuals Avg. & Std. w.r.t. IGS Cumulative
IGS08, Miami, June 2-6, 2008 N
Consistency:
N&E ~ 2-3mm
H ~ 5-7mm
Avg. (mm)
Std. (mm) E H
Scale=3x

13. IGS08, Miami, June 2-6, 2008
ACs Scale offset
esa new software

14. ACs ERPs Residuals w.r.t. IGS Combined
IGS08, Miami, June 2-6, 2008 Xp Yp
LOD
Xpr
Ypr
Consistency:
LOD ~ 10us
[XY]p ~ mas
[XY]pr ~ mas/d
Excluded:
cod [XY]p, [XY]pr
sio [XY]pr

15. ERPs Residuals Between IGS Combined and Bulletin A
IGS08, Miami, June 2-6, 2008 Xp Yp
LOD
Xpr
Ypr
Bull. A Pole Position Interpolated to mid-day
Bull. A Pole Rate estimated from Pole position
LOD
(us) Xp
.01mas Yp
.01.mas
Xpr
.01mas/d
Ypr
Avg -1 -4 5 -2
Std 18 4 11 12

16. IGS Combined Weekly Apparent Geocenter
IGS08, Miami, June 2-6, 2008 Y X
Offset ~2mm
Annual Period
X&Y ~4mm
Z ~5mm Z
Scale=2x

17. ACs Apparent Geocenter Residuals and Std. w.r.t. IGS Weekly
IGS08, Miami, June 2-6, 2008 X
Consistency:
X&Y ~ 5mm
Z ~ 10mm
Res. (mm)
Std. (mm) Y
Excluded:
gfz
ngs (until wk 1476) Z
Scale=2x
Scale=2x

18. Summary (1/2) Reference Frame Stations Network of stations:
IGS08, Miami, June 2-6, 2008
Reference Frame Stations
106 Active
15 Discontinuities
11 dormant + not operational
Network of stations:
60 – 250 (+) per AC
~350 stations combined
Some AC Parameters Excluded
ERPs : cod ([XY]p, [XY]pr) ; sio ([XY]p)
Geocenter : gfz, ngs (until wk 1476)

19. Summary (2/2) ACs Coordinates Consistency w.r.t.:
IGS08, Miami, June 2-6, 2008
ACs Coordinates Consistency w.r.t.:
IGS05 (N-E ~ 3 mm, H ~ 9 mm)
IGS Weekly (N-E ~ 1-2 mm, H ~ 3-4 mm)
IGS Cumulative (N-E ~ 2-3 mm, H ~ 5-7 mm)
ACs ERP’s Consistency:
LOD ~ 10us
( [XY]p ~ mas; [XY]pr ~ mas/d)
Bull A. & IGS ERPs:
LOD -1 ± 10 us
Xp&Yp -4&+5 ± 5mas ; Xpr&Ypr -2&0 ± 12mas/d
ACs Geocenter Consistency:
X&Y ~5 mm; Z ~ 10mm
AC’s Residual Time Series have small bias w.r.t. each other.

20. IGS08, Miami, June 2-6, 2008
Some Issues
Provide warning or separate solutions when changes that can affect the products do occur (Usually done)
When a change in Antenna type occur, logs and ACs databases need to be updated quickly, so proper calibration is applied.