Optimizing satellite operations: uncertainty modeling and integration in constellation scheduling
Tutor/a - Director/a
Gallardo Duval, Isabel
Estudiant
Gallardo Duval, María Isabel
Tipus de document
Projecte Final de Màster Oficial
Data
2024
rights
Accés restringit per acord de confidencialitat
Editorial
Universitat Politècnica de Catalunya
UPCommons
Resum
The emergence of satellite constellations for telecommunications has notably increased in the recent years, enhancing the accessibility to space, and making satellite networks indispensable. The integration of Non-Terrestrial Networks (NTN) with Terrestrial Networks (TN) and the optimization of their management has become essential. This study focuses on addressing the uncertainties posed by this challenge, with particular emphasis on the unpredictability of traffic generation. In satellite operations, the focus on managing uncertainties has been mostly within Earth Observation (EO) applications, while in telecommunications scenarios, uncertainties (and specifically, those related to the unpredictable nature of traffic generation) have not been addressed as extensively. In this work, an analysis of the main uncertainty sources in satellite networks has been performed, and they have been aggregated into three main aggregated sources based on modeling similarities: satellite failure, link quality, and traffic model. These aggregated sources are described with a Weibull probabilistic distribution for satellite failure, bounded limits on the window duration for the link quality, and a generalized methodology for the integration of stochastic traffic models. In addition, an uncertainty management model has been designed. The proposed methodology for traffic generation is validated within an extensive framework that includes network-related metrics and constraints to optimize task scheduling. The steps for incorporating stochastic variables into the optimization process are described in detail, and a new optimization parameter is introduced: the schedule certainty. The impact of the schedule certainty is evaluated in an Internet of Things (IoT) scenario. Furthermore, the uncertainty model implementation and validation is performed in a constellation management tool for 5G/6G technologies, the Constellation Management System (CMS). The results compare the former CMS to the probability aware (P-aware) CMS. The findings show how the P-aware scheduling maintains a precise level of certainty consistent with operator-defined thresholds, providing greater certainty for the same performance metrics compared to the baseline CMS. This framework supports satellite operators in dynamically adjusting service coverage and system efficiency by means of stochastic information provided by the traffic model. To the best of our knowledge, this is the first time that such an analysis has been performed in the context of task scheduling for a satellite communication application. The insights gained from this study offer valuable contributions to optimizing operations in complex satellite networks.
Entitat col·laboradora
Fundació i2cat
Professorat participant
- Gallardo Duval, Isabel