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Optimal Coverage Of Theater Targets With Small Satellite Constellations, Axel Rendon
Optimal Coverage Of Theater Targets With Small Satellite Constellations, Axel Rendon
Theses and Dissertations
The daylight passes of a low-Earth orbit satellite over a targeted latitude and longitude are optimized by varying the inclination and eccentricity of an orbit at different altitudes. This investigation extends the work by Emery et al, in which the optimal Right Ascension of the Ascending Node was determined for a circular, matched inclination orbit. The optimal values were determined by a numerical research method based on Emery et al's Matlab program. Results indicate that small increases in inclination raise the number of daylight passes up to 33%. These optimal inclinations depend on the satellite semi-major axis. Eccentricity increases also …
Covariance Estimation And Autocorrelation Of Norad Two-Line Element Sets, Victor P. Osweiler
Covariance Estimation And Autocorrelation Of Norad Two-Line Element Sets, Victor P. Osweiler
Theses and Dissertations
This thesis investigates NORAD two-line element sets (TLE) containing satellite mean orbital elements for the purpose of estimating a covariance matrix and formulating an autocorrelation relationship. Orbit propagation is performed using Simplified General Perturbations Number 4 (SGP4) analytical model as implemented within Satellite Took Kit. For a given satellite, TLEs from a span of two weeks are used to calculate position and velocity differences of estimated state vectors in order to characterize their variance behavior and compute a covariance matrix for the most recent TLE. Six satellites and eight time spans are investigated, with all state vector differences evaluated in …