Neutral Density and Crosswind Determination from Arbitrarily Oriented Multiaxis Accelerometers on Satellites

摘要

An iterative algorithm for determining density and crosswind from multiaxis accelerometer measurements onnsatellites is presented, which works independently of the orientation of the instrument in space. The performance ofnthe algorithm is compared with previously published algorithms using simulated data for the challengingnminisatellite payload.Without external error sources, the algorithm reduces rms density errors from 0.7 to 0.03%nand rmswind errors from38 to 1 m=s in this test.However, the effects of the errors in the instrument calibration andnthe external models that are used in the density and wind retrieval are dominant for the challenging minisatellitenpayload. These lead to mostly systematic density errors of the order of u000110–15%. The accuracy of the wind resultsnwhen using the newalgorithmis almost fully determined by the sensitivity of the cross-track acceleration componentnto the calibration and radiation pressure modeling errors. The applicability of the iterative algorithm and thenaccuracy of its results are demonstrated by presenting challengingminisatellite payload data froma period in whichnthe satellite was commanded to fly sideways and by comparing the density and wind results with those fromadjacentndays for which the satellite was in its nominal attitudemode. These investigations result in recommendations for thendesign of future satellite accelerometer missions for thermosphere research.