Antenna radiation effects on the orbits of GPS and INTELSAT satellites

• Published in: Acta astronautica 2013-07, Vol.88, p.1-7
• Main Authors: Heilmann, A., Ferreira, L.D.D., Dartora, C.A., Nobrega, K.Z.
• Format: Article
• Language: English
• Subjects: Antenna radiation; Antennas; Artificial satellite; Conservation; Global Positioning System; GPS; INTELSAT; Intelsat satellites; Mathematical models; Orbits; Perturbation; Satellite navigation systems; Satellites
• ISSN: 0094-5765; 1879-2030
• DOI: 10.1016/j.actaastro.2013.02.009

A large number of disturbances add to the main force exerted by Earth's gravitational field and affect the actual orbital trajectory of artificial satellites. They possess antennas with specific purposes, such as telecommunication systems operating at specific ranges of frequencies and radiated power. For instance, the antennas used in the GPS and INTELSAT satellites are quadrifilar helix and parabolic reflectors respectively. The radiation emitted by the antennas produces a radiation reaction force on the satellite making its orbital elements deviate from their expected values. Using a mathematical model for the radiation reaction force caused by the antenna, derived from the electromagnetic theory and the energy-momentum conservation law, the perturbation effects on the orbits of the GPS and INTELSAT satellites were studied. The numerical integrator used to solve the satellite equations of motion is based on the Runge–Kutta method of fourth and fifth orders. The theoretical model of antenna radiation reaction takes into account the satellite mass, antenna radiated power and maximum gain of the antenna. ► The effect of antenna radiation reaction on the satellite motion is considered. ► A mathematical model is based on the electromagnetic theory and conservation laws. ► NRT coordinate deviations are non-negligible and amounts to a few metes in some cases. ► Specific examples of BLOCK IIR-11 and INTELSAT 907 were studied.