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Geoscience Australia 02 February 2006
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VLBI network design
Australian Government
Geoscience Australia
NGRS Workshop, 1-2 February, Canberra
Geoscience
Australia02 February 2006
Geoscience
Australia02 February 2006
Radiotelescopes in Australia
Geoscience Australia
02 February 2006
Radiotelescopes in Australia
Geoscience Australia
02 February 2006
New network benefit
Geoscience Australia
02 February 2006
- ICRF (0.1 mas)
ITRF (1 mm)
network of small size fast moving dishes
IVS
Australian
more data
more sources
Australian geodetic datum
better reference sourcepositions
GPS
SLR
New dish/network design benefit
Geoscience Australia
02 February 2006
Model sXp sYp sUT1 sNut1 sNut2 chi-sq Number (μas) (μas) (μsec) (μas) (μas) of scans____________________________________________________________________________ 6 stations 118 98 4.1 233 82 2.024 3290
6 st + Hartrao 101 61 4.2 168 60 1.646 3179
6 st + Hobart 81 69 3.4 156 61 1.657 3442
6 st + Yarra 58 59 2.7 133 47 1.693 3739
6 st + Y&Hob 58 54 2.7 133 45 1.646 4181
6 st + Y&Hart 43 47 2.5 116 43 1.553 3542
Geoscience
Australia02 February 2006
Hobart,26-meterantenna
Too far from all other radiotelescopes;Limited amount of good radiosources in the southern hemisphere;Slow slew rate (1 deg/sec) – little data;Old design
New radiotelescope design
Geoscience Australia
02 February 2006
- Small size (< 20 meter);
- High slew rate (> 5 deg/sec);
- Near real-time VLBI;
- New equipment (broad band receiver 1-32 GHz);
- 5 deg elevation angle limit
Scheduling
Geoscience Australia
02 February 2006
- sharing time between astronomical VLBI and geodetic VLBI
- 50/50
- IVS makes schedule on annual basis
- ATNF makes schedule on semiannual basis - at least one Australian site each calendar day - own time assignment committee?
Geoscience
Australia02 February 2006
Heght differencesNy-Alesund
Year
1994 1996 1998 2000 2002 2004 2006m
eter
-0.15
-0.10
-0.05
0.00
0.05
0.10
0.15
TRF daily difference time series
Height componentKokee
Year
1992 1994 1996 1998 2000 2002 2004 2006
met
er
-0.15
-0.10
-0.05
0.00
0.05
0.10
0.15
Geoscience
Australia02 February 2006
TRF daily difference time series
Height component,Hobart
Year
1988 1992 1996 2000 2004
met
er
-0.15
-0.10
-0.05
0.00
0.05
0.10
0.15
Height componentHartrao
Year
1984 1988 1992 1996 2000 2004
met
er
-0.15
-0.10
-0.05
0.00
0.05
0.10
0.15
