GPS

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Geodesy, GPS GIS
Prof. Dr. Muhammed SAHIN http//atlas.cc.itu.edu.
tr/sahin
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COURSE DESCRIPTION

• Introduces students to spatial concepts that are
  important in the planning, construction, and
  operation of civil engineering projects and
  activities.
• The expression of these concepts in graphical
  language, which is central to civil and
  architectural communication, will be introduced
  by first developing some basic skills in CAD.
• Concepts and principles of location and layout of
  points on the surface of the three-dimensional
  earth will be studied from both an historical and
  a modern technology perspective. .

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COURSE DESCRIPTION

• The problem of converting the curved surface of
  the earth onto a plane map or computer screen
  will be covered. The use of plane concepts for
  local layouts will be covered along with a study
  of the circumstances under which two-dimensional
  plane concepts can be utilized.
• The technological basis for modern measurement
  and positioning systems such as DME and GPS will
  be discussed and demonstrated. Techniques used to
  identify and lay out land areas in the United
  States will be covered.
• Finally, an introduction to GIS will be
  introduced and demonstrated.

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COURSE OBJECTIVES

• This course is intended to introduce students to
  spatial concepts, which are important in the
  planning, design, construction and operation of
  Civil Engineering projects and activities, and
  which require precise spatial measurement or
  location of points on the earth or in space.
• Such projects can be local, such as related to
  the construction of a building or might cover a
  large extent such as studying the spatial
  features of a coastline or river, the extent or
  spread of an environmental problem or
  constructing a tunnel under the English Channel.
• Concepts and principles of location and layout of
  points on the surface of the 3-dimensional earth
  will be studied from both a historical and modern
  technology perspective.

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COURSE OBJECTIVES

• The problem of converting the curved surface of
  the earth onto a plane map or computer screen
  will be covered.
• The use of plane concepts for local layouts will
  be investigated along with a study of the
  circumstances under which 2-dimensional plane
  concepts can be utilized in Civil Engineering
  layout.
• An introduction to GIS technology will be
  included and students will be assigned small
  projects in this area.
• The technological basis for modern measurement
  and positioning systems, such as GPS will be
  developed and firms active in these areas and
  possessing state-of-the-art equipment will be
  asked to provide a demonstration of some of these
  techniques.
• The methods used to identify and layout land
  areas in Turkey will be covered.

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COURSE TEXTBOOK

• Barry F. Kavanagh Surveying - Principles and
  Applications, Sixth Edition

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Geodesy

• study of the size shape of the Earth
• determination of earth gravity field
• variation of earth surface
• precise positioning
• study of geodynamics (polar motion,
• earth rotation crustal deformation)
• performs all the objectives stated above using
• the earth orbiting satellites, including Moon and
• extra-galactic radio sources known as quasars.

Satellite geodesy, or space geodesy
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The World, 200 million years ago
NASA 1999
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Artificial Satellites in Space
Hight above earth (km) Satellite types
150 - 1 500 Remote sensing 1 500 - 20
000 Geodetic gt36 000 Communication
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Forces acting on a satellite
Moon
Sun
Earth-reflected radiation pressure of Sun
Asmospheric drag
Earth Ocean Loading
Direct radiation pressure of Sun
Non-spehericity of Earth
Earth
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Atmosphre
20 000 km
200 km
Ionosfer
Tropospher
50 km
Cloud
Earth
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History of Navigation Satellite Systems
1957 Launch of first satellite, SPUTNIK by former
Soviet Union 1957 TRANSIT system by USA 6 orbit
planes, 6 satellites, 1100 km above the
earth 1967 ZIKADE system by former USSR 6
orbit planes, 6 satellites, 1100 km above the
earth 1974 GPS by USA 6 orbit planes, 24
satellites, 20200 km above the earth 1976 GLONASS
by former USSR 6 orbit planes, 24 satellites,
20200 km above the earth 2000 GALILEO
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History of Laser Ranging Systems

• Satellite Laser Ranging (SLR), 1964
• Lunar Laser Ranging (LLR), 1964

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Satellite Laser Ranging (SLR)
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SLR Operation
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Satellite Laser Ranging (SLR)
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Laser satellites

• Starlette ( France, 1975 )
• Lageos-1 ( US, 1976 )
• Ajisai (Japan, 1986)Etalon-1,2 ( USSR, 1989
  )Topex/Poseidon ( US/Fr, 1992 )Lageos-2 (
  US/Italy, 1992 )Stella ( France, 1993 )

GPS-35,36 ( US, 1993/94 )Glonass-63,67 ( Russia,
1994 )ERS-2 ( ESA, 1995 )GFZ-1 ( 1996
)MIDORI/ADEOS (Japan,1996)TiPS ( US, 1996 )
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LAGEOS
LAser GEOdynamic Satellite
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Most Commonly used satellites
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Laser stations used at ITU
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Lunar Laser Ranging (LLR)
Laser reflectors on the Moon
LLR observatories
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Lunar Laser Ranging (LLR)
Wettzell - Germany
McDonald - USA
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LLR targets on the Moon
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Very Long Baseline Interferometry (VLBI)
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International VLBI operations
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VLBI Antennas
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