Synthetic Aperture Radar
Synthetic-aperture radar (SAR) is a form of radar whose defining characteristic is its use of relative motion, between an antenna and its target region, to provide distinctive long-term coherent-signal variations, that are exploited to obtain finer spatial resolution than is possible with conventional beam-scanning means. It originated as an advanced form of side-looking airborne radar (SLAR).
SAR is usually implemented by mounting, on a moving platform such as an aircraft or spacecraft, a single beam-forming antenna from which a target scene is repeatedly illuminated with pulses of radio waves at wavelengths anywhere from a meter down to millimeters. The many echo waveforms received successively at the different antenna positions are coherently detected and stored and then post-processed together to resolve elements in an image of the target region.
Current (2010) airborne systems provide resolutions to about 10 cm, ultra-wideband systems provide resolutions of a few millimeters, and experimental terahertz SAR has provided sub-millimeter resolution in the laboratory.
SAR images have wide applications in remote sensing and mapping of the surfaces of both the Earth and other planets. SAR can also be implemented as "inverse SAR" by observing a moving target over a substantial time with a stationary antenna.
Read more about Synthetic Aperture Radar: Relationship To Phased Arrays, Typical Operation, Image Appearance, Origin and Early Development (ca. 1950–1975), Algorithm, More Complex Operation, Data Collection
Other articles related to "synthetic aperture radar, radar, aperture, synthetic":
... Interferometric synthetic aperture radar, also abbreviated InSAR or IfSAR, is a radar technique used in geodesy and remote sensing ... This geodetic method uses two or more synthetic aperture radar (SAR) images to generate maps of surface deformation or digital elevation, using differences in the phase of the ...
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... in providing data and services based on Synthetic Aperture Radar imagery ... The GlobeSAR program included the collection of airborne Synthetic Aperture Radar (SAR) imagery in Europe, the Middle East, Africa, and the Asia/Pacific region ... purpose of GlobeSAR was to strengthen the capability of the participating countries to use radar data in resource management applications, and to prepare for the use of data ...
... as a prototype for instruments to be flown on the NASA Space Shuttles, NASA operated a synthetic-aperture radar on a NASA Convair 990 ... The Space Shuttle has also carried synthetic-aperture radar equipment during the SIR-A and SIR-B missions during the 1980s, as well as the Shuttle Radar Laboratory (SRL) missions in 1994 and ... surface of Venus over several years using synthetic-aperture radar ...
... Interferometric synthetic aperture radar (InSAR) is a radar technique used in geodesy and remote sensing ... This geodetic method uses two or more synthetic aperture radar (SAR) images to generate maps of surface deformation or digital elevation, using ...
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