Integration of sensors for photogrammetry and remote sensing

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Integration of sensors for photogrammetry and
remote sensing

• 8th semester, MS
• 2005

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Course overview

• Introduction to RS
• Image geometry, georeferencing,
  orthorectification
• Platforms for optical sensors
• Microwave sensing
• Digital airborne cameras, ALS

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Introduction to remote sensing

• RS principle
• Electromagnetic energy
• Sources of energy
• Interaction with atmosphere and Earth surface
• Ideal and real RS system
• Optical sensors for RS
• Photographic systems
• Digital sensors
• Multispectral sensors
• Hyperspectral sensors

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Remote sensing principle

• Information about an object, area, or phenomenon
  is obtained through the analyses of data acquired
  by a device that is not in contact with the
  object, area, or phenomenon under investigation
  (Lillesand)
• Specifically
• Data collected by sensors detecting elmg. energy
  that are operated from airborne or spaceborne
  platforms
• Goal
• inventory, mapping, and monitoring earth
  resources

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Remote sensing principle
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Reference data
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• sources of energy
• propagation though the atmosphere
• interaction with Earth surface
• re-transmition through the atmosphere
• sensing systems
• sensing products
• interpretation and analysis
• information products
• users

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Energy interactions in the atmosphere

• Scattering
• unpredictable diffusion of radiation by particles
  in the atmosphere
• Rayleigh scatter blue sky, haze in imagery
• Absorption
• mainly due to water vapor, carbon dioxide, and
  ozone
• atmospheric windows

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Energy interactions with Earth surface features

• EI(?)ER(?)EA(?)ET(?)
• EI(?) incident energy
• ER(?) reflected energy
• EA(?) absorbed energy
• ET(?) transmitted energy
• Reflectance
• specular
• diffuse (most interesting in RS)

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Energy interactions with Earth surface features
Spectral reflectance ?? ER(?)/ EI(?)
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Detection of elmg. energy

• photographically
• light-sensitive film (silver halide crystals)
• range 0.3 0.9 µm (from UV to near IR)
• high spatial resolution and geometric fidelity
• electronically
• CDDs (charge coupled devices), A-to-D signal
  conversion
• broad spectral range
• electronic storage, transmittance, and processing
  of data
• Sensing systems
• active
• passive

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Ideal RS system

• uniform energy source
• noninterfering atmosphere
• unique energy interactions at earths surface
  features
• sensor highly sensitive to all wavelengths with
  high spatial resolution
• real-time data processing
• advanced data users

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RS projects

• Definition of the problem
• Evaluation of the potential of RS techniques for
  solving the problem
• Appropriate data acquisition (including reference
  data needed)
• Data processing and interpretation procedures
• Quality evaluation of results

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Examples of RS applications

• Mapping (DEM, topographic mapping)
• Environmental engineering
• Geology
• Hydrology (soil moisture, glacier dynamics
  monitoring)
• Agriculture (crop type mapping, crop monitoring)
• Forest engineering (species identification)
• Disaster management (burn mapping, floods)
• Examples
• Advantege of
• multispectral, multiresolution, multitemporal data

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Multispectral scanners

• Range of sensing 0.3 - 14µm (UV, visible,
  near-IR, mid-IR and thermal IR), several narrow
  bands
• Across-track scanner Along-track scanner

• Linear array of detectors
• Focal plane of the image
• Lens
• GSD

• Oscillating mirror
• Detectors
• IFOV
• GSD
• Angular field of view
• Swath

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Example LANDSATs TM

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Example LANDSATs TM
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Hyperspectral imaging

• Range of sensing from visible to mid-IR
• Hundreds of detectors measuring in narrow bands,
  typically 0.4 2.4 µm
• AVIRIS (Airborne Visible/Infrared Imaging
  Spectrometer)

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Hyperspectral imaging
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Hyperspectral imaging
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Spectral libraries
http//speclib.jpl.nasa.gov/
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Links

• Remote sensing tutorials
• NASA
• http//rst.gsfc.nasa.gov/Front/tofc.html
• Ohio university
• http//dynamo.phy.ohiou.edu/tutorial/tutorial_file
  s/frame.htm
• Canada centre for RS
• http//www.ccrs.nrcan.gc.ca/ccrs/learn/tutorials/f
  undam/chapter1/chapter1_1_e.html
• Remote sensing glossary
• http//www.casde.unl.edu/vn/glossary/intro.htm
• http//www.ldeo.columbia.edu/res/fac/rsvlab/glossa
  ry.html