A method for determining look-angle stability parameters for VSAT control systems installed on ships with a non-orthogonal axis system

The VSAT communication depends on many factors, such as signal strength, receiver sensitivity, and environmental interference factors. To ensure optimal signal quality, the VSAT antenna must remain properly aligned and polarized toward the satellite. For the VSAT system installed on the shipboard, the disturbances from waves, wind, and current significantly disrupt the antenna's ability to maintain a stable orientation toward the satellite target. To enhance structural efficiency, motion precision, and stiffness, some shipboard VSAT systems, such as the ORSAT AL7103 and AL7107, incorporate designs with motion axes that are not perpendicular. The article introduces a method for calculating look angle stability parameters for this type of VSAT system, including azimuth and elevation angles, rotation control angles, and the ship's attitude angles. Some experiment and simulation results support the theoretical analysis of the proposed method.