Sensor
Topic: Remote Sensing, GIS and GNSS · NCERT: Class 11, Ch 6 "Introduction to Remote Sensing"
Meaning
A sensor is a device that receives electromagnetic radiation (energy travelling as waves) and turns it into a signal. That signal is shown as a photographic or digital image. Sensors are of two kinds. Photographic sensors (cameras) record the scene on film. Non-photographic sensors (scanners) record it as digital numbers. The sensor is one of the three basic elements of remote sensing, along with the object surface and the energy waves.
Example
Indian Remote Sensing satellites carry LISS cameras. LISS-III on IRS-1C (1995) had 23 m cells. These sensors record reflected energy over India in several bands for mapping crops, forests and water.
Don't confuse with
- Platform: this is the carrier, such as an aircraft, drone or satellite. The sensor is the recording device mounted on it.
Related concepts
- Photographic sensor
- Multispectral scanner
- Swath
- Whiskbroom scanner
- Instantaneous field of view
- Pushbroom scanner
- Passive and active remote sensing
- Radar
- Synthetic aperture radar
- LiDAR