1. REMOTE SENSING
SHREE SWAMI ATMANAND SARASWATI
INSTITUTE OF TECHNOLOGY

2. PREPARED BY:
Prof. Karm Balar

3. REMOTE SENSING(GIS)
 Definition of Remote sensing
 Advantages Of Remote sensing
 Elements of Remote sensing
 Limitation of Remote sensing
 Principal Of Remote Sensing

4. DEFINITION OF REMOTE SENSING
 Remote sensing is the science of gathering
information from a location that is distant from the
data source. Image analysis is the science of
interpreting specific criteria from a remotely sensed
image.
 assistance of computer enhancement, extract
information from an image, whetherit is furnished in
the form of an aerial photograph, a multispectral
satellite scene, a,
 radar image, a base of LIDAR data, or a thermal
scan.

5. HOW TO WORK REMOTE SENSING

6. ADVANTAGES OF SATELLITE SCENES
Presuming that the inherent
accuracy of satellite data conforms
to the mapping
specification demands, satellite data
can be a valuable tool in many
ways.

7. REMOTE SENSING (1)
Active: E’
emitted and
return is
measured (e.g.,
radar, sonar)

8. PICTORIAL IMAGE CHANGE DETECTION
 Satellite raster imagery
provides a pictorial
simulation that can be
overlaid on
 GIS/LIS vector themes so
that the viewer can see the
image and line drawing
 simultaneously. Hardcopy
plots of the image data
can be created.
 satellite imagery for
different pasHistorical
ses over the same site
is available for
 purchase. Change
detection information
can be gleaned from
these time-lapse
scenes.

9. BASIC PHOTO FORMAT

10. SATELLITE SYSTEMS
Geostationary Satellite
in equatorial orbit at
36,000 km altitude
stays over the same spot
Satellite
Polar-Orbiting Satellite
about 850 km altitude travels over
both north and south poles. Earth
rotates ~13° for each ~100 min orbit
can see whole globe at
high resolution
Sees only small portion

11. Landsat
1 (1972)
3 m high; 1.5 m diameter
890 kg
solar cells 1.2 x 2.4 m
3-axis stabilized
multi-spectral scanner
return beam vision
viewed continuous strip of 185
km.
scan mirror oscillated 13 times a
second

12. Land sat a Multi-
Spectral
Scanner images of
Rondonia, Brazil at
higher resolution show
the detailed interaction
of development and
deforestation.
Resolution of these
images is 80 m.

13. Cloud parameters
Dark gray
clouds
in IR photograph
represent the
highest
and thickest
clouds
Individual
storms show
as dark patches
surrounded by
light regions
A. Visible (reflected) B . Infra-Red (E=sT4)

14. LIMITATION OF REMOTE SENSING
I. remote sensing system the variation in classes to be discriminated is
expressed by the distribution of their member populations in spectral
space, e.g., as illustrated in two bands,
II. b1, b2. The extent of overlap between two classes expresses their
fundamental inseparability.

16.  Variation in different components of the system, such as
benthic class
spectral variation, variance in water clarity, or sensor noise,
contributes to variation in the
recorded signal.sensor limited objectives are those for which
change in sensor

17. PASSIVE & ACTIVE REMOTE SENSING

18. PRINCIPLES OF REMOTE SENSING
 Detection and discrimination of objects or surface features means
detecting
 and recording of radiant energy reflected or emitted by objects or surface
 material (Fig. 1). Different objects return different amount of energy in
different
 bands of the electromagnetic spectrum, incident upon it. This depends on
 the property of material (structural, chemical, and physical), surface
roughness,
 angle of incidence, intensity, and wavelength of radiant energy.
 The Remote Sensing is basically a multi-disciplinary science which
includes
 a combination of various disciplines such as optics, spectroscopy,
photography,
 computer, electronics and telecommunication, satellite launching etc. All
these

19. STAGES IN REMOTE SENSING
 • Emission of electromagnetic radiation, or EMR
(sun/self- emission)
 • Transmission of energy from the source to the surface of
the earth, as well
 as absorption and scattering
 • Interaction of EMR with the earth’s surface: reflection
and emission
 • Transmission of energy from the surface to the remote
sensor
 • Sensor data output

20. REMOTE SENSING PROCESS
What we see
At temperature above absolute zero, all
objects radiate electromagnetic
energy by virtue of their atomic and
molecular oscillations. The total amount
of emitted radiation increases with the
body’s absolute temperature and peaks
at progressively shorter wavelengths. The
sun, being a major source of energy,
radiation and illumination, allows
capturing reflected light with conventional
(and some not-so-conventional) cameras
and films.

21. MODERN REMOTE SENSING TECHNOLOGY
VERSUS CONVENTIONALAERIAL
The use of different and extended portions of the
electromagnetic
spectrum, development in sensor technology,
different platforms for remote
sensing (spacecraft, in addition to aircraft),
emphasize on the use of spectral
information as compared to spatial information,
advancement in image
processing and enhancement techniques, and
automated image analysis in
addition to manual interpretation are points for

22. THANK YOU