Occasion determination method of low Earth orbit satellites meeting the narrow-beam signal

The determination of the occasion when the low Earth orbit satellite meets the narrow-beam signal is quite important. Based on the orbit prediction model of simplified general perturbations 4 (SGP4), the calculation model of the relative position between the low Earth orbit satellite and the ground target is established in the paper, and so is the calculation model of the relative position between the low Earth orbit satellite and the high Earth orbit communication satellite. The determination method of the occasion when the low Earth orbit satellite meets the narrow-beam signal is further proposed. It is shown by the simulation results that the proposed calculation method possesses high accuracy and feasibility and is able to satisfy the practical application requirements.