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Pointing Knowledge for SPARCLE and Space-Based Doppler Wind Lidars in GeneralThe SPAce Readiness Coherent Lidar Experiment (SPARCLE) will fly on a space shuttle to demonstrate the use of a coherent Doppler wind lidar to accurately measure global tropospheric winds. To achieve the LOS (Line of Sight) accuracy goal of approx. m/s, the lidar system must be able to account for the orbiter's velocity (approx. 7750 m/s) and the rotational component of the earth's surface motion (approx. 450 m/s). For SPARCLE this requires knowledge of the attitude (roll, pitch and yaw) of the laser beam axis within an accuracy of 80 microradians. (approx. 15 arcsec). Since SPARCLE can not use a dedicated star tracker from its earth-viewing orbiter bay location, a dedicated GPS/INS (Global Positioning System/Inertial Navigation System) will be attached to the lidar instrument rack. Since even the GPS/INS has unacceptable drifts in attitude information, the SPARCLE team has developed a way to periodically scan the instrument itself to obtain less than 10 microradian (2 arcsec) attitude knowledge accuracy that can then be used to correct the GPS/INS output on a 30 minute basis.
Document ID
Document Type
Conference Paper
Emmitt, G. D.
(Simpson Weather Associates, Inc. Charlottesville, VA United States)
Miller, T.
(NASA Marshall Space Flight Center Huntsville, AL United States)
Spiers, G.
(NASA Marshall Space Flight Center Huntsville, AL United States)
Date Acquired
August 19, 2013
Publication Date
November 1, 1999
Publication Information
Publication: Tenth Biennial Coherent Laser Radar Technology and Applications Conference
Subject Category
Instrumentation And Photography
Distribution Limits
Work of the US Gov. Public Use Permitted.
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