System-Level Interference Analysis between LEO Mega-Constellations

With the large-scale construction of low Earth orbit (LEO) mega-constellations (such as Starlink, OneWeb, etc.) worldwide, due to the scarcity of frequency bands and the increasingly tight orbital space, the problems of mutual influence within constellations and between different constellations have become increasingly serious. To solve these problems, this paper studies a multi-level Walker-Delta layout method for LEO constellations. Based on the consideration of the relationship between time and space, a global interference calculation method is proposed. Combining orbital mechanics and the direction pattern of antennas, the interference amount generated by satellites at different orbital altitudes on ground relay stations is given. Simulations show that the interference is not the same everywhere, there are certain differences in latitude, and it also varies in time. Especially for high-latitude regions, the signal-to-interference-noise ratio will drop significantly and even fall below 5 dB; while in mid-low latitude regions, the situation is good. This has certain guiding significance for spectrum sharing coordination and anti-interference beam formation.