Perturbation of Electromagnetic Radiation of Downlink in Orthogonal Components on the GOES 16 Satellite by Planar Antenna Phase Array

Abstract

The Geostationary Operational Environmental Satellite - GOES 16 has an arrangement of planar antennas for uplink and downlink communications in the L-band range, UHF frequency (1694,3/1694,9 MHz), 16 W transmission power and a planar antenna array gain of 28 dBi, for communication operations and data scanning. The structure of antennas in the form of arrangement combines high directivity in the electromagnetic signal and reduction of the broadside, which corresponds to a smaller angular variation. Assuming a communication channel for the GOES 16, from the phase arrangement of planar antennas using 4 rectangular radiant elements of 30 cm × 30 cm (patch) in the transmission (downlink), we defined an expression for the gain of the array of planar antennas and model an acceleration for the satellite, due to the effect of the electromagnetic perturbation it admits, antenna theory and the energy-momentum conservation laws. For a state vector - 04/02/2019, at 18h 40m 12.44s, we implemented a routine using numerical methods with the equation of movement in the form of Cartesian components, which can be used for both keplerian movement as well as adding the desired disturbing accelerations. We propagate its orbit over a period of 5 days, with a step of 10 minutes, and correlate the results of this propagation in the propagated orbital model without disturbance and with the disturbance of the acceleration on the satellite of electromagnetic origin, centered in the phase arrangement of flat antennas. The perturbative effect of this model is applied on GOES 16 taking into account satellite mass, antenna characteristics, radiated power and maximum antenna gain. The numerical integrator used for the solution of the satellite motion equation is based on the fourth and fifth degree Runge-Kutta method, and the results shows that the phase arrangement of planar antennas with the described configuration implies a significant electromagnetic disturbance, changing the components in the direction (radial, transverse and normal) and the coordinates XYZ.