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INDIAN INSTITUTE OF SURVEYING AND MAPPING

HYDERABAD

PRESENTATION ON:-

REMOTE SENSING SENSORS

BY:- SAURABH SINGH

M.TECH .z 1ST YEAR

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REMOTE SENSING

³Science´ and ³art´ of acquiring information (spectral, spatial, temporal)

about material objects, area, or phenomenon.

Without coming into physical contact with the object.

³In remote sensing´, information transfer is accomplished by use of 

electromagnetic radiation (EMR).

 A satellite with remote sensors to observe the earth is called RS satellite,

or EO satellite.

Remote-Sensing

Satellites are

characterized by

their 

Altitude,

Orbit and

Sensor.

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Remote Sensing Sensor Technology

What is a sensor ?

What sensors consist of ?

How they perform or work (operate) ?

Types sensors(in detail) ?

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«. continued

What sensors consist of ? Each sensor have-Optical system, Detector and Signal processor.

For Optical-mechanical sensor -

Physically moving mirrors or lenses

  Analog signal Digital signal

For Charge ± coupled sensor -

Light sensitive material embedded in a Si chip.

Manufactured to be very as small as 1µm.Sensitive to visible and near IR radiation.

Sensor consist of linear array of CCD also 2D arrays (1000

separate sensors).

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«. continued

How sensors perform or work (operate) ?

Light energy

Limited time

Exposure of 

CCD

SENSOR

Charge ±coupled

sensor 

sun

Information

is read

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«. continued

Types sensors(in detail) ?1) Depending upon the source of energy

continued«..

Sensor Type

Passive

Non scanningNon imaging

Microwaveradiometer 

Magnetic sensor and

Gravimeter 

Imaging Cameras

Infrared,

Monochrome

Natural Color 

 Active

Non scanningNon Imaging

aser Distance Meter 

Microwave Altimeter 

ScanningImaging

Image PlanSensing

Phased Arrayradar 

Object PlanSensing

Real ApertureRadar 

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«. ContinuedTypes sensors(in detail) ?

1) Depending upon the source of energy

Active Sensor 

Own source of energy.

Not depend external source of 

energy.

Work day and night.

Un-seasonal.

Eg. Radar, Altimeter,Laser scanner(Lidar)

Passive Sensor 

Not have own source of energy.

Depend on external energy.

Seasonal.

Work in day only.

Best time 10:30 AM ± 2:30PM.

Eg. Radiometre,Thermal Scanner,Image spectrometer,Aerial

Photogrametry.

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«. Continued

Types sensors(in detail) ?3) Depending upon the scanning system.

Sensor Types

Whiskbroom

Scanner 

Pushbroom Scanner 

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«. Continued

Types sensors(in detail) ?3) Depending upon the scanning system.

a)Whiskbroom or Cross-track Scanner(Single Detector)The essential components are

1) a light gathering telescope.

2) appropriate optics (e.g., lens).

3) a mirror.

4) spectroscope to break the

incoming radiation into spectral

intervals.

5) a means to direct the light so

dispersed onto an array or bank of 

detectors.6) an electronic means to sample the

photo-electric effect.

7) a recording component.

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«. Continued

Types sensors(in detail) ?3) Depending upon the scanning system.

b)Pushbroom or Along-track Scanner(Array of Detector) The IFOV of each detector sweeps a path

parallel with the flight direction

The essential components are

1) small sensitive detectors stacked side

by side appropriate optics (e.g., lens)

2) no mirror.

3) detector is a charge-coupled device .

4) pixels that will eventually make up the

image .

5) an electronic means to sample thephoto-electric effect.

6) a recording component.

Eg. Landsat Multispectral Scanner.

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Some Examples of Sensors

RESOURCESAT-2: It will have imaging sensors similar to RESOURCESAT-1.

RESEOURCESAT-3: it carry more advanced LISS-III-WS (Wide Swath) Sensor.

OCEANSAT-3: Oceasat-3 would carry Thermal IR Sensor, 12 channel Ocean Color 

Monitor,and Passive Microwave Radiometer.

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CONCLUSION Sensor a device gather energy and convert it into suitable signal to

obtained information .

Each sensor  have-Optical system, Detector and Signal processor.

Types of sensor-a) Depending upon the source of energy .

i)Active Sensor ii) Passive Sensor.

b) Depending upon the optical setup for imaging sensor.i)Image Plane ii) Object Plane.

c) Depending upon the scanning system.i) Whiskbroom scanner ii)Pushbroom Scanner 

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QUESTIONS ?