Remote sensing is the branch of
science where information about an object is obtained by proper analysis of
data acquired by a device which is not in contact with the object. Microwave
band is a region of the electromagnetic spectrum with wavelength range mm-m.
This band can be effectively used for remote sensing. There are two categories
in microwave remote sensing. They are active microwave remote sensing and
passive microwave remote sensing. Active microwave systems provide a self
illumination model. Passive microwave systems record the energy of thermal
origin emitted from materials. Imaging sensors and non-imaging sensors are used
in microwave remote sensing. Most widely used imaging radar is Side Looking
Airborne Radar, SLAR. Radars can be comprised of either real aperture or
synthetic aperture. In the real aperture system, beam
width and antenna size determines the resolution of the system. Synthetic
aperture system yields better resolution due to the superlative signal
processing techniques. Some factors which affects the microwave measurements
are surface roughness, radar backscattering coefficient and radar wavebands.
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