Banca de DEFESA: Téssio Perotti Arruda

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : Téssio Perotti Arruda
DATE: 31/05/2024
TIME: 14:00
LOCAL: VIDEOCONFERÊNCIA
TITLE:

Optimizing 3D Antenna Arrays and Ground Station Distribution for Satellite Communication

KEY WORDS:

Antenna Arrays, Satellite Communication, Ground Station Distribution, Convex Optimization, Differential Evolution, Link Budget.

PAGES: 156
BIG AREA: Engenharias
AREA: Engenharia Elétrica
SUMMARY:

This work investigates the design and optimization of 3D antenna arrays and ground station distribution for satellite communication systems. It has the objective of proposing a ground station distribution that maximizes the contact and downlink data with a LEO satellite over a given territory. The dissertation begins with a theoretical foundation, reviewing key antenna types such as parabolic reflectors and microstrip antennas. It discusses radiation fields from apertures and directivity from electric fields, providing essential background information. The study then explores satellite propagation and link budgets, analyzing factors such as transmitted power, free space losses, signal-to-noise ratio and satellite link quality. Ground station distribution is addressed through a multi-step problem analysis, where the distribution across Brazil is assessed to determine optimal locations for effective satellite communication. Various optimization algorithms, including convex optimization, sequential least squares, and differential evolution, are employed to model and optimize ground station distribution, with a focus on improving overall network performance. The next chapter introduces an approach to antenna array design that allows antennas to be positioned and steered in any 3D configuration. It begins with a discussion on physically steered arrays, where the relative positions, feed coefficients, and rotations of individual antennas are defined. The chapter provides equations to compute the resulting electric fields, illustrating these concepts with practical examples and simulation results. Is then proposed an approach focusing on creating arrays with specific patterns, using optimization algorithms to achieve constant field strength across a range of angles. A final section explores a design for considering satellite passes, optimizing a fixed-position array to track the trajectory of a specific satellite. Finally, it is presented the overall conclusions and considerations regarding the found results. First, it is proposed a ground station distribution that maximizes link coverage with a specific satellite over a given territory. Second, the scenario is slightly modified to consider ground station that are constrained to specific places. In this case, the variable to be optimized to maximize the satellite link coverage are the antenna parameters, like the diameter of a parabolic reflector. Lastly, it is proposed an antenna array design that maintains constant power level in the direction of a satellite pass with no moving parts.

COMMITTEE MEMBERS:
Externo à Instituição - ALLAN KARDEC DUAILIBE BARROS FILHO - UFMA
Interno - 3157968 - DANIEL COSTA ARAUJO
Interno - 1848167 - RENATO ALVES BORGES
Presidente - 2193312 - SEBASTIEN ROLAND MARIE JOSEPH RONDINEAU