Fundamentals of Remote Sensing

Definition: The process of collecting information about an object or area from a distance, typically using satellites or aircraft.
Purpose: To observe and measure physical properties without direct contact.

Electromagnetic Radiation (EMR):
- Definition: Energy that travels through space in the form of waves.
- Sources: Sun (natural) and artificial sources (e.g., radar).
- Interaction with Objects: EMR can be absorbed, transmitted, or reflected by objects.
Spectral Bands:
- Visible Light: Wavelengths visible to the human eye (400-700 nm).
- Infrared: Beyond visible light, used for heat detection.
- Microwave: Used in radar remote sensing.
Resolution:
- Spatial Resolution: The size of the smallest object that can be detected (e.g., 10 meters).
- Spectral Resolution: The ability to distinguish between different wavelengths.
- Temporal Resolution: How frequently data is collected for the same area.
- Radiometric Resolution: The sensitivity of the sensor to detect slight differences in energy.

Data Acquisition:
- Sensors: Instruments on satellites or aircraft that collect data.
- Platforms: Vehicles carrying sensors (e.g., satellites, drones).
Data Processing:
- Preprocessing: Correction of sensor errors, atmospheric effects, and geometric distortions.
- Image Analysis: Techniques like classification, change detection, and image enhancement.
- Post-Processing: Converting processed data into useful information (e.g., maps, reports).

Environmental Monitoring: Tracking changes in land cover, vegetation, and water bodies.
Agriculture: Monitoring crop health, soil conditions, and irrigation.
Disaster Management: Assessing damage from natural disasters and planning recovery efforts.
Urban Planning: Analyzing urban growth, infrastructure development, and land use patterns.