16-07-2011, 03:25 PM
PRESENTED BY,
NAFEENA NAZEER
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What is SAR system ?
Synthetic Aperture Radar (SAR) is one of the most useful of the remote sensing strategies used by research scientists and operation specialists in a variety of fields.
SAR is an active sensor.
It is originated as an advanced form of side-looking airborne radar SLAR.
SAR System
SAR is an imaging radar system that sends a microwave pulse to the surface of the earth and register the reflection from the earth surface.
SAR sensor can collect data even if the observation area is covered with obstacles or an observation is made at night time.
How Can SAR’s Help Map Natural Disasters and Hazards?
Synthetic Aperture Radar is a space or airborne technology that provides high-resolution monitoring for environmental and military purposes in all weather or day/night conditions
With SAR it is possible to obtain detailed information quickly that may be of great use in combating such natural disasters as wildfires, oil spills, ice and seas, etc.
STRUCTURE OF SAR SYSTEM
It consist of
-> Active front end pane
-> Central electronics
-> Electrical ground support
equipment (EGSE)
STRUCTURE OF SAR SYSTEM
The active front-end panel consist of
-> Radiators
->T/R modules
->Panel control electronics
->Panel power conditioner
->Distribution network
->Calibration network
Synthetic Aperture Radar System
Synthetic Aperture Radar System
Synthetic Aperture Radar System
SYNTHETIC APERTURE RADAR SYSTEM
PROCESSING AND STORAGE SUBSYSTEM
Process and store the information obtained from SAR instrument.
The processing stage involves:-
1.Buffering of the SAR raw data
stream in real-time.
2.Off-line image processing &
compression of the buffered SAR
data.
Contd..
3.Mass memory data management and organisation.
4.Reformatting and output of compressed data at downlink rate.
PROCESSING OF IMAGES
APPLICATIONS
Observation of volcanic activities and flood disasters.
Land and Sea monitoring.
Observation of vegetarian growth.
Monitoring of ocean currents and travelling icebergs.
Detection of oil spills in oceans.
ADVANTAGES
Opertional under all weather conditions with the capabilities for sensing the earth day & night.
Provides description of surface texture.
Has own source of illumination.
Cloud & fog cover are not a problem.
Vegetation & subsurface penetration capabilities.
DISADVANTAGES
Image distortion.
Coarse resolution.
Extensive shadowing of areas characterised with relief.
CONCLUSION
SAR have the capability to operate under all weather conditions .
SAR is well established part radar art
>with airborne systems for survelliance and non-cooperative target identification purpose.
>with space-borne systems for geophysical remote sensing applications over oceans,land & polar regions.
Contd..
SAR instruments have been a major focus of research and development during the last few years.
At present it provides only images & in future it will have to deliver dedicated information to each special users.