Age of information in Satellite Networks

Abstract This thesis focuses on optimizing the Age of Information (AoI) in Low Earth Orbit (LEO) satellite networks, where maintaining data freshness is crucial for real-time communication systems. With increasing reliance on satellite constellations for global communication services such as Internet access and disaster monitoring, minimizing AoI has become a key performance objective. The research proposes a framework that integrates predictive scheduling, multi-satellite cooperation, and energy-aware algorithms to optimize AoI in LEO satellite networks. Predictive scheduling leverages satellite trajectory data to forecast handovers and schedule updates at optimal times, while energy-aware algorithms adjust update frequency based on available energy. Multi-satellite cooperation is introduced to distribute communication tasks across satellites, reducing redundancy and improving network efficiency. The key findings of the research demonstrate that predictive scheduling significantly reduces AoI spikes by transmitting updates before satellite handovers, ensuring that real-time data is maintained across the network. Multi-satellite cooperation enhances communication efficiency by allowing satellites to coordinate transmissions and share resources, resulting in lower AoI and optimized energy consumption. Energy-aware algorithms ensure that satellites manage their limited energy resources efficiently, balancing the trade-off between frequent updates and energy conservation. The findings are particularly relevant for large satellite constellations, such as Starlink and OneWeb, which aim to provide global Internet services with low latency. Additionally, the research has significant implications for disaster monitoring systems and other real-time applications where maintaining up-todate information is critical. In conclusion, this thesis demonstrates the importance of AoI optimization in satellite networks and provides a robust framework for improving communication efficiency while ensuring real-time data availability, making it a critical consideration for future satellite communication systems.