Remote Sensing Platforms:

Introduction:

Remote sensing is defined as the science which deals with obtaining information about objects on earth surface by analysis of data, received from a remote platform.

In the present context, information flows from an object to a receiver (sensor) in the form of radiation transmitted through the atmosphere. The interaction between the radiation and the object of interest conveys information required on the nature of the object. In order for a sensor to collect and record energy reflected or emitted from a target or surface, it must reside on a stable platform away from the target or surface being observed.

 

Figure : Remote Sensing Platforms

Platforms:

Platform is a stage to mount the camera or sensor to acquire the information about a target under investigation. Based on its altitude above earth surface, platforms may be classified as

(1) Ground borne
(2) Air borne
(3) Space borne

Ground-based platforms:

The ground based remote sensing system for earth resources studies are mainly used for collecting the ground truth or for laboratory simulation studies.

• Used to record detailed information about the surface which is compared with information collected from aircraft or satellite sensors.

• In some cases, this can be used to better characterize the target which is being imaged by the other sensors, making it possible to better understand the information in the imagery.

• Sensors may be placed on a ladder, scaffolding, tall building, crane, etc. 

Figure 2: Ground-based platforms

Air-borne platforms:

Aircraft’s are generally used to acquire aerial photographs for photo-interpretation and photogrammetric purposes. Scanners are tested against their utility and performance from these platforms before these are flown onboard satellite missions.

•Are primarily stable wing aircraft, although helicopters are occasionally used.

•To collect very detailed images and facilitate the collection of data over any portion of the Earth's surface at any time.

Figure 3: Air-borne platforms

Space-borne platforms:

Platforms in space are not affected by the earth's atmosphere. The closed path of a satellite around the earth is called its orbit. These platforms are freely moving in their orbits around the earth, and entire earth or any part of the earth can be covered at specified intervals. The coverage mainly depends on the orbit of the satellite. It is through these space borne platforms, we get the enormous amount of remote sensing data.

Space remote sensing is sometimes conducted from the-Space Shuttle-Satellites (more commonly) 

Satellites are objects which revolve around another object - in this case, the Earth.

e.g: the moon is a natural satellite, whereas man-made satellites include those platforms launched for remote sensing, communication, and telemetry (location and navigation) purposes. 

Figure 4: Space-borne platforms