Inter-Satellite Link-Enhanced Transmission Scheme Towards Aviation IoT in SAGIN
Qian Chen, Chenyu Wu, Shuai Han, Weixiao Meng, Tony Q. S. Quek
TL;DR
The paper addresses content delivery for aviation IoT in a space-air-ground integrated network by leveraging caching at LEO satellites and high-speed laser inter-satellite links. It develops a caching-aware IFC framework and proposes two tailored optimization schemes: an exact penalty method for cached-file satellite association and an alternating optimization approach for non-cached files, incorporating GS bandwidth allocation. Through theoretical development and extensive simulations, the study demonstrates substantial latency reductions when using multiple ISLs, with significant gains from satellite caching and optimized GS resources, particularly for non-cached data. The results highlight practical insights on ISL provisioning, gateway deployment, and LEO altitude choices, underscoring the potential of SAGIN-enabled caching to advance aviation IoT and in-flight connectivity.
Abstract
The rapid development of the aviation Internet of Things (IoT) has positioned in-flight connectivity (IFC) as one of its critical applications. Space-air-ground integrated networks (SAGIN) are essential for ensuring the performance of IFC by enabling seamless and reliable connectivity. However, most existing research treats satellites merely as transparent forwarding nodes and overlooks their potential caching capabilities to enhance IFC data rates. In this article, we explore an IFC-oriented SAGIN where satellites and ground stations (GSs) work together to transmit content to airborne passengers, thereby facilitating airborne communication. By categorizing files into cached (instantly accessible via satellites) and non-cached files (available only through GSs), this article pioneers the integration of multiple inter-satellite links (ISLs) into the IFC framework, thus innovating the content delivery process for both types of files. To minimize the average delay of content delivery, we formulate the corresponding optimization problems: 1) For cached files, we propose an exact penalty-based method to determine the satellite association scheme. 2) For non-cached files, we present an efficient algorithm based on alternating optimization to jointly optimize satellite association and GS bandwidth allocation. Our proposed framework is low in complexity, paving the way for high-speed Internet connectivity for aviation passengers. Finally, simulation results are provided to demonstrate the effectiveness of our proposed IFC framework for SAGIN.