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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