A Satellite Footprint Visualisation Tool

This thesis concerns the development of a numerical software tool for propagating and visualising orbits of artificial bodies orbiting the Earth and the calculation of magnetic conjunctions between these objects and the ground. The developed toolbox Î× ËËØ enables the users to visualise the trajectories of satellites under different parameters and to estimate the visibility of a satellite to maintain efficient satellite ground communication links. The trajectory predictions enables the user to visualise the magnetic conjunctions for " space weather " studies by plotting the northern and southern footprint of the magnetic field line. The satellite's motion results from the analysis of all forces which have an effect on the trajectory of the satellite. The resultant of all forces acting on a satellite is proportional to its acceleration, so it is possible to describe the trajectory of a satellite in the central force field it is acting in. In this case the main acting force is the gravi-tational force. This force is very variable in the near Earth space due to the effect of the Earth's flattening and is therefore very variably marked; it could be characterised by the zonal harmonics. The equations to describe the motion of a satellite arises from Kepler's empirically laws and Newton's mathematical description afterwards. The major focus here lies on Newton's law of universal gravitation and Newtons second law of motion. These laws leads to a description of the orbital motion by using differential equations, which are only possible to solve analytically when an ideal gravitational force field could be assumed but the Earth is known to neither have an even mass distribution nor be a perfect sphere. Therefore in order to get a precise description of the orbital motion the physical laws have to be expanded.RAD) and implementing the methods, described in this model, in MATLAB r. The determination of the magnetic conjunction is performed by Tsyganenko's magnetic field model (Tsy'03). By means of this model and the numerical representation in MATLAB r the magnetic connection between the satellite and the ground station can be determined. All these models are summarised in three basic functions of Î× ËËØ in order to facilitate a fast numerical calculation of the given equations of motion and field descriptions, so it is possible to receive accurate results which agree with the theory in the context of computed precision.