Different orbit determination algorithms for BİLSAT-1

Ural, Serkan
This study aims to investigate different orbit determination algorithms for the first Turkish remote sensing satellite, BILSAT-1. The micro-satellite carries an onboard GPS receiver. Pseudorange measurements simulated from the position and velocity data supplied by TÜBITAK-BILTEN are used for the implementation of different orbit determination algorithms concluding to an estimate of the satellite̕s state. Satellite̕s position, velocity components and the GPS receiver̕s clock bias are selected as the state parameters to be estimated. Kalman filter algorithms are used for the estimation of these state parameters. The modeled affecting force components include; geopotential and atmospheric drag. The global gravity models EGM96 and EIGEN-CG03C have been utilized together with Harris Priester atmospheric density model for the force modeling. The effect of the changes during the implementation of the force models, numerical integration, and estimation algorithms are investigated. Software has been developed using MATLAB programming language for the implementation of all algorithms performed in this study for orbit determination.


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Citation Formats
S. Ural, “Different orbit determination algorithms for BİLSAT-1,” M.S. - Master of Science, Middle East Technical University, 2006.