1. Remote Sensing
By:-
Manish Solanki(13BCL109)
Rajan Sutariya(13BCL110)
Thakor Jitendra(13BCL111)
Abhisek Thayya(13BCL112)
Soham Trivedi(13BCL113)

2. Outline
1. Basic Concept
2. Principles of radiation
3. Types of system
4. Spectral signatures
5. Resolution
7. Applications
8.Adavantage

4.  Remote sensing is the small- or large-scale
acquisition of information of an object or
phenomenon, by the use of either recording
or real-time sensing device(s) that are
wireless, or not in physical or intimate contact
with the object (such as by way of aircraft,
spacecraft, satellite)
 In practice, remote sensing is the stand-off
collection through the use of a variety of
devices for gathering information on a given
object or area.

5. Remote Sensing Systems:Remote Sensing Systems:
the Human Eyethe Human Eye
• SpectralSpectral Resolution: 0.4-0.7 µm
• SpatialSpatial Resolution: ~ 1-3 cm @ 20 m
• RadiometricRadiometric Resolution: ~16-32 shades
B/W or ~100 colors

7. Remote Sensing: A Definition
"Remote sensing is the science (and to
some extent, art) of acquiring information
about the Earth's surface without actually
being in contact with it.”
This is done by sensing and recording
reflected or emitted energy and processing,
analyzing, and applying that information.

8. Satellite view of BCKVSatellite view of BCKV

9. Types of remote sensing
 Passive: source of
energy is either the Sun
or Earth/atmosphere
 Sun
- wavelengths: 0.4-5
µm
 Earth or its atmosphere
- wavelengths: 3 µm
-30 cm
 Active: source of
energy is part of the
remote sensor system
 Radar
- wavelengths: mm-m
 Lidar
- wavelengths: UV,
Visible, and near
infrared
Camera takes photo as example, no flash and flash

10. Active sensors provide their own
energy source for illumination.Active
Emit radiation
Radiation reflected is
detected and
measured
LIDAR, RADAR, and
SONAR

11. Passive
Sun’s energy which is
reflected (visible) or
Absorbed and re-
emitted as thermal
infrared wavelengths
Landsat,
AVHRR
Remote sensing systems which measure
energy that is naturally available are
called passive sensors

12. Passive
remote
sensing

13. Seven Elements of Remote
Sensing
A.A.
EnergyEnergy
Source orSource or
IlluminationIllumination
For photography, the source is light from the sun. Other types
of remote sensing, such as radar, supply their own energy source

14. Seven Elements of Remote
Sensing
B.B.
Radiation &Radiation &
AtmosphereAtmosphere
Remote sensing is affected by how well the illuminating energy
penetrates the atmosphere. This is especially important when the
distance involved is great, such as from a satellite

15. Seven Elements of Remote
Sensing
C.C.
InteractionInteraction
with Targetwith Target
What the remote sensor is really measuring is how the
energy interacts with the target.

16. Seven Elements of Remote
Sensing
D.D.
Recording ofRecording of
Energy by theEnergy by the
SensorSensor
The sensor records the reflected energy it receives

17. Seven Elements of Remote
Sensing
E.E.
Transmission,Transmission,
Reception,Reception,
andand
ProcessingProcessing
All remote sensing systems have some method of transmitting,
receiving, and processing the data. Some satellites actually drop film
canisters to Earth using parachutes. Most remote sensing is now
done digitally, and the data is transmitted using radio waves.

18. Seven Elements of Remote
Sensing
F.F.
InterpretationInterpretation
andand
AnalysisAnalysis
Computers can do some analysis, but the final
interpretation is up to the human element.

19. Seven Elements of Remote
Sensing
G.G.
ApplicationApplication
Remotely sensed data isn’t much use unless it is
gathered for a purpose or application.

20. A. Energy Source or IlluminationA. Energy Source or Illumination

24. Microwave region from about 1 mm to 1 m.

26. EMR
 Modern physics acknowledges dual nature of
EMR
 The wave-particle duality refers to how EMR
of differing wavelengths behaves, not what it is
 Low frequency EMR tends to act more like a
wave; higher frequency EMR tends to act
more like a particle

27. The Nature of Light
 In the 1860s, the Scottish mathematician and physicist
James Clerk Maxwell succeeded in describing all the basic
properties of electricity and magnetism in four equations
 This mathematical achievement demonstrated that electric
and magnetic forces are really two aspects of the same
phenomenon, which we now call electromagnetism

28. Wave Model
 Wavelength and frequency are related to the
speed of light as follows: c = λv; λ = c/v; v =
c/λ
•EMR travels as a set of sinusoidal orthogonal harmonic
waves travelling at the speed of light, (c = 3.0x108ms-1
)
Low frequency EMR tends
to act more like a wave;
higher frequency EMR tends
to act more like a particle

29. Particle Model
 EMR is comprised of tiny particles (quanta) called
photons travelling in a wave-like pattern at the speed of
light
 Intensity is proportional to number of photons
 Total amount of energy is related to wavelength and
frequency by Planck’s constant (h):
Q = hv
Q = hc/λ
where : Q = energy of a quantum

30. The Foundation of RS
 Differences in how features interact with and
emit EMR allow us to distinguish between objects
based on their unique spectral characteristics or
signatures
 Variations are wavelength dependant; some things
may “look” the same at certain wavelengths but
different in others

31. Adavantage
Remote sensing makes it possible to collect data
on dangerous or inaccessible areas and
Remote sensing also replaces costly and slow data
collection on the ground, ensuring in the process
that areas or objects are not disturbed.
Other uses include different areas of the earth
sciences such as natural resource management,
agricultural fields such as land usage and
conservation.

32. All alone in ourneighborhood of spaceAll alone in ourneighborhood of space
Apollo 12’s Classic Earth Rise from Moon

33. Ikonos 1 m panchromatic imageryIkonos 1 m panchromatic imagery
20002000

34. MODIS Land Reflectance andMODIS Land Reflectance and
Sea Surface TemperatureSea Surface Temperature

36. Depending almost exclusively on imaging capabilities,
"spy satellites" have activities. Visible,
Near-Infrared; Thermal Infrared, and Radar sensors
are applied to gathering been orbited by the hundreds
(by several countries) to gather military intelligence
or information about terrorist information about ground
targets and activities of national security significance .
,
TESAR IMAGE OF PENTAGON,U.S.A

38. Of course, picking up changes over large areas and long
time spans is just one of many uses that space imagery is
being put to. As an example here is a classification of major
ground cover types in part of one county (Monmouth) in
New Jersey just south of Sandy Hook. Its specific purpose
was to define the surface characteristics that could affect
water quality planning in the Navesink Watershed. This
map was made using Landsat MSS imagery.

39. A given scene imaged at different times of the year can
show great variety. Changing Sun angles, atmospheric
variations, seasonal differences in vegetation cover,
presence of snow, and other variables will produce often
pronounced contrasts in the spectral responses that
determine "how an image looks". This is evident in this
montage of 6 Landsat MSS images of an area in the
desert of Utah.

40. Here is a plot of
the global
distribution of the
ionosphere,
measured by the
Jason-1 satellite
(pages 8-7 and
14-12) whose
prime mission is
to measure Sea
Surface Heights.

41. The image is made by HENA
( High Energy Neutron Atom )
sensor to show the density variations
of hot plasma around the Earth .

42. This illustration is a two-dimensional cutaway sketch of
streamlines representing solar wind particles as they passed
through Earth's magnetic field.