Lesson 1 of 0
In Progress

Sources of EO Data

This lesson is about ….



Passive Systems

  • Rely on the illumination of the Earth by the sun (or artificial light sources)
  • Detect the reflection from the Earth’s surface
  • Are very sensitive to cloud cover
  • Need no internal energy source

Active Systems

  • Provide illumination by sending out microwaves
  • Are largely weather (cloud) independent
  • Acquire images during day and night
  • Actively control wavelength, frequency and polarisation of the transmitted signal