1 Observations. Sat05_71.ppt, 2005-11-28. Directions: satellite visible with stars as background....

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Observations. Sat05_71.ppt, 2005-11-28.

• Directions: • satellite visible with stars as background.• Direction to radio-source (VLBI)

• Directions and distances: if satellite carries reflectors

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Stellar-triangulation. Sat05_71.ppt

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Global network. Sat05_71.ppt

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West-European Network.sat05_71.ppt

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North-American Network:

First results for Greenland

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Distances. Sat05_71.ppt, 2005-11-28.

Reflected light: Lasers – 2-ways.

SLR= Satellite Laser Ranging.

http://ilrs.gsfc.nasa.gov/

http://www.eos-aus.com/satellite_laser_ranging.htm

Satellite emits signal: 1 way or two ways.

http://www.gfz-potsdam.de/pb1/op/prare/prare.html

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Laser http://msl.jpl.nasa.gov/QuickLooks/lageosQL.html

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LAGEOS

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Earth-Moon system

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Distance measurements. Sat05_71.ppt, 2005-11-28.

Signal:

Impuls:

Phase:

waves.ofnumber integer N

distance.way -2 ,)(2

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Nrij

λ Δλ

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Integer ambiguity. Sat05_71.ppt, 2005-11-28.

N may be determined using

• Signal with several frequencies

• Several observations

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Distance-differences. Doppler. Sat05_71.ppt, 2005-11-28.

.Observations:

)( and )( 3221 tBtBtBtB

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Satellite Altimetry. Sat05_71.ppt, 2005-11-28.

Geos-3, GSFO

SEASAT

Topex/Poseidon, Jason,

ERS1 + 2, Envisat

and

CRYOSAT

Satellite

Water – Ice - Plains

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Satellite-to-Satellite Tracking. Sat05_71.ppt, 2005-11-28.

CHAMP, from GPS to satellite

GRACE. from GPS to two satellites and ranging between the satellites

GOCE, from GPS to the satellite

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Interferometry. Sat05_71.ppt, 2005-11-28.

http://www.jb.man.ac.uk/vlbi/

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VLBI. Sat05_71.ppt, 2005-11-28.

http://lupus.gsfc.nasa.gov/brochure/bintro.html

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Results. Sat05_71.ppt, 2005-11-28.

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