Investigation of the Influence of LEO Constellation Dynamics on Optical Inter-satellite Links

Low Earth orbit (LEO) satellite constellations are seen as a future extension of today’s terrestrial fiber networks, providing network services in remote and underserved areas. In order to achieve true, seamless connectivity on a global scale, satellites need to employ inter-satellite links (ISLs) to connect with each other within the constellation, thus creating a meshed network. In this paper, we present a pragmatic analysis to the operation of optical ISLs in a LEO constellation by examining the line-of-sight dynamics between satellites and providing in-sight into the impact these dynamics have on the design and operation of optical terminals for the ISLs. The results show that maintaning East-West-bound data traffic with an optical ISL are challenging not only in terms of link fluctuations, but also handover conditions that can lead to link outages. The findings highlight the considerations needed for designing an optical terminal as well as the potential networking challenges for routing the traffic within a LEO constellation.