Department of Geomatics Remote Sensing Principles and Applications

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Department of Geomatics Remote Sensing
Principles and Applications

• RADAR REMOTE SENSING

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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote
SensingSYDNEY
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Department of Geomatics Remote Sensing
Principles and ApplicationsRadar Remote Sensing

• Uses microwave (cm to meter scale) wavelengths
• Atmosphere very transparent
• Clouds and haze do not interrupt image.

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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote
Sensing

• Side-looking beam provides range.
• Forward motion provides azimuth
• Range time delay converted to distance (Time by
  the speed of light)

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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote
Sensing

• Azimuth resolution determined by pulse width
• Range resolution determined by beam width
• Beam width inversely proportional to antenna size
• Fine resolution requires large antenna

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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote
Sensing

• Synthetic aperture radar overcomes this
  resolution limitation by using Doppler
  information.

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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote
Sensing

• Image Distortions
• Caused by time variations due to topography
• Foreshortening
• Layover
• Radar Shadow

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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote
Sensing

• Reflection either diffuse or specular
• Backscatter dependent on incidence angle
• Multiple reflectance modes

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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote Sensing

• White Aa
• Green Vegetation
• Red Apoe poe

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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote Sensing

• Radar imaging has control of
• Frequency
• Incidence angle
• Polarisation
• Illumination direction

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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote Sensing

• X band Red
• C band Green
• L band Blue

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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote Sensing

• Polarisation
• HH
• HV
• VV
• VH

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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote
SensingRaw L-band Image
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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote Sensing

• Red Plane polar
• Green Cross polar
• Blue Combination

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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote Sensing
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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote Sensing
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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote Sensing

• RADAR Interferometry
• Uses change in phase
• Caused by differences in incidence angle
• Detects topography
• Caused by differences in time
• Detects changes in height or position
• Needs stable orbit and good position information

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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote Sensing
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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote Sensing
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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote
SensingCANBERRA
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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote
Sensing

• USA RADAR Spacecraft
• Seasat
• SIR-A
• SIR-B
• SIR-C
• Light SAR

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Department of Geomatics Remote Sensing
Principles and Applications Radar Remote
Sensing

• Other RADAR Spacecraft
• ERS -1,2
• JERS-1
• Radarsat
• Almaz