3. Introduction OF MSS
• Defination :-MSS is define as the collection of
reflected, emitted and backscattered energy from an
object in multiple bands of electromagnetic spectral
OR
•
Multispectral remote sensing is
generally based on acquisition of image data
of Earth's surface simultaneously in multiple
wavelengths.
4. Types OF MS Remote Sensing
• We Use Mainly Three Types Detector in mss
(a) Line detector
(b) Wishkbroom
(c) Pushbroom
(d)
(a) Line Detector :•
In Line Detector sensor detect
only one object at a time
6. Wiskbroom OR Cross-track
In whiskbroom a mirror of fixed size rotates along an
axis and the energy received from the ground is
focused on to a spectrometer or grating for dispersion
into different spectral bands. After dispersion the
reflected radiation is focused on an array of
photovoltaic cells and energy sensed in different
spectral bands is than calibrated.
The widely used cross-track
scanning system employ a faced mirror that is rotated
by an electric motor, with an horizontal axis of
rotation aligned parallel with the flight direction.
9. Along-track or Pushbroom scanning
These sensors do not use opto-mechanical device
and have no moving parts. The energy coming from
ground directly falls on the array of charge-coupled
devices {CCD), which calibrate the received energy
and change it to digital counts. This method allows
sensing of energy for larger time and hence results in
better signal.
• GIFOV :- Ground projected instenteneous FOV
• GSI :- Ground projected sample interval
• FOV :- Fieeld of view
• IFOV :- Instenteneous field of view
• GFOV :- Ground projected field of view
11. Circular scanning
The scan motor and mirror are mounted with a
vertical axis of rotation that sweeps a circular
path on the terrain. Only forward motion of the
sweep is recorded to produce images. An
advantage of this system is the distance between
scanner and terrain is constant and all the ground
resolution cells have the same dimension.
Circular scanners are used for reconnaissance
purposes in helicopters and low flying aircrafts.
The axis of rotation is tilted to point forward and
acquire images of the terrain well in advance of
the aircraft position.
12. APPLICATION OF MSS
1. In Military :- To gather military intelligence or
information about terrorist information about ground
targets and activities of national security significance .
2. IN Medical :-Most medical remote sensing is designed
to "see into" the body without having to be invasive
(cutting it open).
3. X-Ray :- Tomographic imagery is the outcome of a CAT
Scan which today is a widely used means of imaging
primarily the body's soft parts
4. -Land Assessment
5. -Tostudy seasonal variation
