Signal Occlusion-Resistant Satellite Selection for Global Navigation Applications Using Large-Scale LEO Constellations

Abstract

With the continuous construction of large-scale Low Earth Orbit (LEO) constellations, their potential for Global Navigation Satellite System (GNSS) applications has been emphasized. This study aims to derive an optimal positioning configuration formula based on the ratio of high-elevation and low-elevation satellites, which can improve the positioning accuracy and overcome the accuracy loss due to signal occlusion. A genetic algorithm is used to solve the optimal positioning configuration problem for large-scale satellite selection. Through a simulation using Starlink satellites currently in orbit, it is verified that the traditional recursive algorithm cannot be applied to satellite selection for large-scale constellations. The proposed formula has a similar accuracy to the Quasi-Optimal algorithm when there is no signal occlusion and the satellites are uniformly selected. However, the accuracy of the latter deteriorates significantly under signal occlusion. Our algorithm can effectively overcome this problem. Moreover, we discuss the effect of different types of obstructions on the accuracy loss. We find that the Quasi-Optimal algorithm is more sensitive to a single large-angle obstruction than multiple small-angle obstructions. Our proposed formula can reduce the localization accuracy degradation caused by signal occlusions in both scenarios.

Navigation Resource Allocation Algorithm for LEO Constellations Based on Dynamic Programming

“…Utilizing LEO constellations for navigation enhancement could substantially improve the performance of existing satellite navigation systems [2]. According to a survey of the current LEO constellations, building a LEO navigation enhancement system based on LEO global communication constellations is one of the mainstream solutions in the future, such as Iridium, SpaceX, OneWeb, and Hongyan [3]. Thus, optimizing the use of satellite resources in LEO constellations to enhance navigational capabilities while minimizing communication bandwidth usage becomes imperative.…”