age of information (AoI); beyond diagonal reconfigurable intelligent surface (BD-RIS); Low earth orbit (LEO) satellite; Markov decision process; meta-learning; Q-learning propagation (QProp); Age of information; Average ages; Beyond diagonal reconfigurable intelligent surface; Ground terminals; Low earth orbit satellites; Markov Decision Processes; Metalearning; Q-learning; Q-learning propagation; Reconfigurable; Computer Networks and Communications; Electrical and Electronic Engineering
Abstract :
[en] This study focuses on downlink transmissions of a low earth orbit (LEO) satellite, assisted by a beyond diagonal reconfigurable intelligent surface (BD-RIS) to serve ground terminals. Toward optimizing the performance of this system, we formulate the minimization of the average age of information (AoI) achieved at ground terminals. Our formulation respects the power budget of the LEO satellite and guarantees the quality-of-service of ground terminals by optimizing the downlink transmit power at the LEO satellite and reflection coefficients at the BD-RIS as decision variables. Owing to its non-convex and tightly-coupled nature, we reformulate the problem as a Markov decision process which effectively captures its dynamics. Next, a Q-learning propagation (Q-Prop) agent is trained to optimize the decision variables. In light of the mobility of ground terminals as well as LEO satellite, this communication system is highly dynamic. Therefore, we enhance the trained Q-Prop model with meta-learning strategy, which augments its adaptability and generalization to system variances. Numerical results indicate that, in comparison to RIS-lacking and RIS-assisted counterparts, our optimised solution achieves 38% and 26% lower average AoI, respectively.
Disciplines :
Computer science
Author, co-author :
Zarini, Hosein; Texas A&m University, Corpus Christi, United States ; Sharif University of Technology, Tehran, Iran
Kazemi, Seyed Mohsen; Texas A&m University, Corpus Christi, United States ; Sharif University of Technology, Tehran, Iran
Sookhak, Mehdi; Texas A&m University, Corpus Christi, United States
Uysal, Elif; Middle East Technical University, Turkey
CHATZINOTAS, Symeon ; University of Luxembourg > Interdisciplinary Centre for Security, Reliability and Trust (SNT) > SigCom
External co-authors :
yes
Language :
English
Title :
Age of Information in LEO Satellite Communications Supported by BD-RIS
Publication date :
26 September 2025
Event name :
ICC 2025 - IEEE International Conference on Communications
Event organizer :
IEEE
Event place :
Montreal, Can
Event date :
08-06-2025 => 12-06-2025
By request :
Yes
Audience :
International
Main work title :
ICC 2025 - IEEE International Conference on Communications
Editor :
Valenti, Matthew
Publisher :
Institute of Electrical and Electronics Engineers Inc.
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