Accession Number : ADA262905


Title :   SWAT II Overview. Revision 1.


Descriptive Note : Project rept.,


Corporate Author : MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB


Personal Author(s) : Parenti, Ronald R ; Everett, Patrick N ; Kramer, Robert ; Page, Daniel A


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a262905.pdf


Report Date : 10 Mar 1993


Pagination or Media Count : 99


Abstract : All adaptive optics systems incorporate devices designed to measure and compensate phase distortions that accumulate over the propagation path of an optical beam. Measurement of the wavefront is accomplished with the aid of a bright source, or beacon, which must be accurately positioned along the beampath. In some scenarios of interest no physical beacon exists; for instance, the propagation of a laser beam to an exoatmospheric object moving at velocity upsilon requires that the beacon lead the target by an angle 2 v/c. In the early 1980's it was proposed that laser backscatter in the atmosphere might provide a suitable alternative source in such cases. Although a synthetic beacon generated in this manner can be placed arbitrarily in angle, any range discrepancy between the target and the beacon can lead to a form of measurement error known as focal anisoplanatism. Lincoln Laboratory's SWAT (Short-Wavelength Adaptive Techniques) program was initiated in 1983 to provide experimental verification of the most promising synthetic beacon concepts and to quantify the magnitude of the associated focal anisoplanatic errors. The test plan for this program includes passive imaging experiments using single and binary stars, as well as active experiments in which a scoring beam will be projected to rocket and satellite targets.


Descriptors :   *MIRRORS , *OPTICAL DETECTION , *LASERS , *BEACONS , *ADAPTIVE OPTICS , TEST AND EVALUATION , SCENARIOS , PATHS , ATMOSPHERIC MOTION , BACKSCATTERING , RAYLEIGH SCATTERING , BINARY STARS , ROCKETS , WAVEFRONTS , SHORT WAVELENGTHS , OPTICAL TRACKING , DISTORTION , TARGET DETECTION , ARTIFICIAL SATELLITES , ERRORS , LASER BEAMS , TARGETS , OPTICAL IMAGES , TURBULENCE , OPTICS , MEASUREMENT , VELOCITY


Subject Categories : Lasers and Masers
      Optical Detection and Detectors
      Optics


Distribution Statement : APPROVED FOR PUBLIC RELEASE