Building Earth Observation Cameras

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4

Earth Observation Camera: An Overview

4.1 Introduction

The information collected by Earth observation cameras is meant to iden-

tify and map various Earth surface objects. This activity is known as remote

sensing and the instruments used to collect the data are called remote sen-

sors. Remote sensors can be broadly classied as passive sensors and active

sensors. Sensors that sense natural radiation, either emitted or reected

from the Earth, are called passive sensors. It is also possible to produce elec-

tromagnetic radiation of a specic wavelength or band of wavelengths as

a part of the sensor system and the interaction of this radiation with ...