EES5053, fall 2005

http://www.utsa.edu/LRSG/

 

Course Review (Nov. 28)

Hongjie Xie

Earth and Environmental Science

University of Texas at San Antonio

 

  

 The EM spectrum is the heart of the class. If you understand EMR, you understand almost half of the remote sensing.

 

    1. EMR

  1. Wave and particle model:
  2. Source of EMR (Mblackbody = s Tkin4,  lmax=2897/ Tkin )
  3. EMR and matter interactions (absorption, transmission or refraction, scattering, reflection), path
  4. Spectral reflectance and albedo

    2. Remote sensing platforms

  1. Ground, Airplane, Satellite
  2. Advantages and disadvantages
  3. Sun-synchronous polar, non-Sun-synchronous, geostationary.

    3. Photogrammetry (0.3-1.0 mm)

  1. Camera
  2. 1 or 4 bands
  3. Two important filters: Haze (remove UV), Yellow (remove blue and UV)
  4. Vantages points
  5. Orthophotos (due to resolution change s = f/h)

    4. Detector configurations

  1. Discrete detectors and scanning mirrors, Linear array, Area array
  2. Across track and along track
  3. Dwell time
  4. FOV and IFOV

    5. Resolutions

  1. Spatial, spectral, radiometrical, temporal
  2. Pixel, pixel value, pixel location

    6. Passive remote sensing (Sun, Earth, or atmosphere)

  1. Multi-spectral (0.4-2.5 µm): Landsat, MODIS, AVHRR

  2. Hyperspectral (0.4-2.5 µm): AVIRIS, Hyperion

  3. Thermal (3-5, 8-14, 6-50 µm):

(1)   all material emit thermal energy (Trad, Tkin, e)

(2)   remote sensor (TB, T or land surface temperature, Planck equation)

 

             d.   Microwave (0.034 cm - 4.3 cm): Atmosphere, ocean, and land emit microwave energy

                                 (1) 89 GHz, 36.5 GHz, 22.2 GHz, 18.7 GHz, 10.7 GHz (X), 6.9 GHz (C)

                                 (2) SSM/I (Special Sensor Mirowave/Imager)

                                 (3) TMI (TRMM Microwave Imager)

                                 (4) AMSR-E (Advanced Microwave Scanning Radiometer - EOS)

                                        - Snow depth and snow water equivalent

                                        - Radio-frequency interference (RFI)

                                 (5) Advantages and disadvantages           

 

    7. Active remote sensing (energy from sensor)

  1. Radar (0.75 cm - 1 m - 231 m)

(1)   Azimuth, look, range, depression angle, polarization

(2)   Ra, Rr

(3)   Roughness, penetration ability, shadow, speckle, banding

(4)   Real Aperture Radar (1 - 11 m)

        - NEXRAD (8.5m antenna, S-band, 10 cm, 3 GHz),

        - TRMM PR (2.1m antenna, Ku-band, 2.17 cm, 13.796 and 13.802 GHz)

(5)   Synthetic Aperture Radar (SAR) (600 m - 15 km)

        - SIR-A, B, C; JERS-1; ERS-1; RADARSAT; AIRSAR/TOPSAR (C band to P band)

(6) Others

        - GPR (75 cm, 400 MHz; 3 m, 100 MHz)

        - SHARAD (15 m, 20 MHz, up to 1 km deep)

        - MARSIS (55 m-231 m, 5.5 MHz - 1.3 MHz, up to 2.5 km deep)

(7)   InSAR (elevation and surface displacement; one SAR two antennas, one SAR in different times) (interferometric Synthetic Aperture Radar)

(8) Advantages

 

    1. Lidar (0.3-0.4, 0.4-0.7, 0.7-1.1)

(1)   Ranger finders (elevation)

(2)   DIAL (gas concentration)

(3)   Doppler (velocity of a target)

(4)   Raman (gases species)

    8. Applications

  1. Remote sensing of Mars

           -History of Mars remote sensing

           -Current missions

           -Some current results

 

    b. Remote sensing of urban landscape

            - Users

            - Given different users, you should have some ideas on what spatial and temporary resolution imagery should be used

 

    c. Remote sensing of vegetation

            - Why (climate, ecology, hydrology, agriculture, and forest

            - What do we measure (Vegetation type, Fractional vegetation cover, health status, LAI)

            - How do we do (chlorophyll absorption, atmospheric water absorption, vegetation indices)

 

    d. Remote sensing of soil moisture

            - In situ

            - Microwave (passive and SAR)

            - Optical (visible and near infrared)

 

    e. Remote sensing of snow and ice

            - Snow depth and snow water equivalent (AMSR-E)

            - Sea ice and ice sheet (ICESat)

            - Snow cover (MODIS: MOD10A1 and A2, C1 and C2)

 

    f. Remote sensing of precipitation

            - In situ

            - Visible and Near Infrared (AVHRR, RainSat)

            - Thermal (Geostationary, GOES)

            - Passive microwave (SSM/I, TMI)

            - Active microwave (NEXRDA, TRMM PR)

    9. Image processing related

  1. Byte, integer, floating
  2. Image stored as raster
  3. BSQ, BIP, BIL
  4. Band math, statistics, link, gray or color image (true- or false-color), spectral curve and spectral library
  5. Atmospheric correction, radiance, reflectance, NDVI
  6. Radiance, brightness temperature
  7. 3D view by draping image and vector overlaying DEM
  8. Unsupervised and supervised classification
  9. Change detection