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Platforms in Remote Sensing


In remote sensing, a platform is the physical structure or vehicle that carries a sensor (camera, scanner, radar, etc.) to observe and collect information about the Earth's surface.

Platforms are classified mainly by their altitude and mobility:

Ground-Based Platforms

  • Definition: Sensors mounted on the Earth's surface or very close to it.

  • Examples: Tripods, towers, ground vehicles, handheld instruments.

  • Applications:

    • Calibration and validation of satellite data

    • Detailed local studies (e.g., soil properties, vegetation health, air quality)

  • Strength: High spatial detail but limited coverage.

Airborne Platforms

  • Definition: Sensors carried by aircraft, balloons, or drones (UAVs).

  • Altitude: A few hundred meters to ~20 km.

  • Examples:

    • Airplanes with multispectral scanners

    • UAVs with high-resolution cameras or LiDAR

    • High-altitude balloons (stratospheric platforms)

  • Applications:

    • Local-to-regional mapping

    • Disaster assessment (floods, landslides, forest fires)

    • Precision agriculture, urban planning

  • Strength: Flexible deployment, high resolution, cloud-free data (depending on altitude).

Spaceborne Platforms (Satellites)

  • Definition: Satellites carrying remote sensing sensors orbiting the Earth.

  • Altitude: Typically 200 km – 36,000 km.

  • Types of Orbits / Platforms:

    1. Low Earth Orbit (LEO)

      • Altitude: ~200–1000 km

      • Examples: Landsat, Sentinel, SPOT, IRS

      • Application: Land cover mapping, agriculture, disaster monitoring

    2. Medium Earth Orbit (MEO)

      • Altitude: ~1000–35,000 km

      • Example: Navigation satellites (GPS, GLONASS)

      • Application: Positioning and navigation

    3. Geostationary Orbit (GEO)

      • Altitude: ~36,000 km, orbit period matches Earth's rotation

      • Example: GOES, INSAT, Meteosat

      • Application: Weather and climate monitoring, continuous observation

  • Strength: Large area coverage, repetitive observations, long-term monitoring.


  • Ground-based → local, detailed, used for calibration.

  • Airborne → regional, flexible, high-resolution (e.g., UAV, aircraft).

  • Spaceborne → global/regional, systematic, used for large-scale monitoring.

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