CBL - Campus del Baix Llobregat

Projecte llegit

Títol: Optimizing Satellite Operations: Uncertainty Modeling and Integration in Constellation Scheduling

Estudiants que han llegit aquest projecte:

Director/a: RINCÓN RIVERA, DAVID

Departament: ENTEL

Títol: Optimizing Satellite Operations: Uncertainty Modeling and Integration in Constellation Scheduling

Data inici oferta: 27-09-2023     Data finalització oferta: 27-04-2024


Estudis d'assignació del projecte:
    MU AEROSPACE S&T 21
    MU MASTEAM 2015
Tipus: Individual
 
Lloc de realització: Fora UPC    
 
        Supervisor/a extern: Arnau Singla Manau
        Institució/Empresa: I2Cat Foundation
        Titulació del Director/a: MSc in Aeronautics, PhD in Network Eng.
 
Paraules clau:
Non-Terrestrial Network (NTN), satellite networks, constellation management, NB-IoT, scenario modeling, uncertainty
 
Descripció del contingut i pla d'activitats:
At i2CAT, a satellite operations planner is being developed for constellations acting as NTN. The idea is to apply task allocation methods (typically used for Earth observation missions) to telecommunications scenarios, specifically for providing IoT services. Some of the challenges (among others) include system heterogeneity, scenario uncertainties, limited resources, the integration of business policies into operations management, and the integration of the planner with a standard core network (3GPP compliant operations). We already have an initial version of this planner that has been systematically validated (unit tests) as well as in a realistic scenario. Among the tasks that continue in the development of this planner, there are two that may be of interest to undergraduate and master's students for their theses.

Firstly, an exhaustive study needs to be conducted on how the various implemented parameters of the planner affect the optimized plans obtained. An example of this would be how prioritizing different users affects the metrics of the optimized plans (latency per user, data transferred, etc.). Additionally, it's necessary to compare the results obtained with i2CAT's planner with other constellation management mechanisms (using the same relevant metrics). The activities to be performed could be as follows:

1. Research the relevant metrics to analyze in the selected scenarios.

2. Design different simulation scenarios to assess how optimization policies affect the results (metrics).

3. Simulate the scenarios with different policies and analyze the results using i2CAT tools and the student's own implementations.

4. Simulate the scenarios and compare the results with other constellation management mechanisms, using i2CAT tools and the student's own implementations.

Secondly, it is necessary to model the inherent uncertainty in the selected scenarios (especially in terms of data generation). There are several methods to do this. The objective of this work package would be to identify these methods, implement a simple method, and validate it through simulations. The activities to be performed could be as follows:

1. Research methods for modeling uncertainty in IoT use cases, with a special focus on data traffic modeling.

2. Identify a simple method applicable to our areas of interest.

3. Implement the selected method in i2CAT software.

4. Validate the selected method using i2CAT tools.

Depending on the motivation and the type of student (undergraduate or master's), it is possible to focus on one part, a combination, or both. There is also the possibility of splitting this proposal into two separate, independent theses proposals for two different students, if necessary.
 
Overview (resum en anglès):
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.

© CBLTIC Campus del Baix Llobregat - UPC