ECI2MeanElements:
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Computes mean orbital elements from reference ECI position and velocity
Since version 7.
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Form:
[elRefMean, dElMean] = ECI2MeanElements(xRefECI, xRelECI, J2);
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Note: it is assumed that all inputs have the same time-tag.
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Inputs
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xRefECI (6,1) reference position & velocity in ECI frame
xRelECI (6,:) relative positions & velocities in ECI frame
J2 (1) size of J2 perturbation
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Outputs
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elRefMean (1,6) mean orbital elements of the reference orbit
dElMean (:,6) mean orbital element differences
NOTE: Both element sets are in Alfriend format [a,theta,i,q1,q2,W]
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References: Terry Alfriend, Texas A&M University
Joe Mueller, Princeton Satellite Systems
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Children:
FormationFlying: Transformation/Osc2Mean
Orbit: OrbitCoord/El2Alfriend
Orbit: OrbitCoord/OrbElemDiff
SC: BasicOrbit/RV2El
