Which component detects radiation and converts it into signals in a remote sensing system?

• A. Sensor
• B. Platform
• C. Processor
• D. Antenna

Answer: (A)

Detecting radiation and turning it into electrical signals is the job of the sensor. In a remote sensing system, the sensor is the device that directly interacts with electromagnetic energy—from visible light to infrared—and converts that energy into electrical signals that can be amplified, digitized, and processed into usable data. The platform merely provides the vehicle carrying the sensor (aircraft, drone, satellite). The processor handles converting the raw signals into images or measurements, and the antenna deals with transmitting or receiving radio-frequency signals, not the initial energy-to-signal conversion. So the sensor is the component that performs the energy detection and conversion.