@MastersThesis{Gomes:2004:DeÓrSa,
author = "Gomes, Vivian Martins",
title = "Determina{\c{c}}{\~a}o de {\'o}rbitas de sat{\'e}lites
artificiais em tempo real atrav{\'e}s da solu{\c{c}}{\~a}o de
navega{\c{c}}{\~a}o de GPS",
school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
year = "2004",
address = "S{\~a}o Jos{\'e} dos Campos",
month = "2004-05-25",
keywords = "engenharia e tecnologia espacial, {\'o}rbita, sat{\'e}lites
artificiais, sistema de posicionamento global, filtro de Kalman,
modelo din{\^a}mico, space technology and engineering, orbits,
artificial satellites, global positioning system, kalman filters,
dynamic model.",
abstract = "O Sistema de Posicionamento Global (GPS) {\'e} um sistema de
navega{\c{c}}{\~a}o por sat{\'e}lites que permite determinar o
posicionamento tridimensional e tempo com alta precis{\~a}o. Seus
principais objetivos s{\~a}o: aux{\'{\i}}lio a
radionavega{\c{c}}{\~a}o, navega{\c{c}}{\~a}o em tempo real,
cobertura global e r{\'a}pida aquisi{\c{c}}{\~a}o de dados
enviados pelos sat{\'e}lites GPS. Prop{\~o}e-se neste trabalho
estimar, em tempo real, o vetor de estado orbital composto de
posi{\c{c}}{\~a}o e velocidade atrav{\'e}s do processamento da
solu{\c{c}}{\~a}o de navega{\c{c}}{\~a}o obtida pelo receptor
a bordo. Al{\'e}m destes fatores, se pretende determinar a
tend{\^e}ncia e a deriva do rel{\'o}gio do receptor GPS a bordo
de sat{\'e}lites. Neste trabalho {\'e} usado o filtro de Kalman
para estimar o vetor de estado baseado nas observa{\c{c}}{\~o}es
do receptor. O filtro de Kalman {\'e} usado devido a sua robustez
em aplica{\c{c}}{\~o}es de tempo real, sem a necessidade de
armazenar observa{\c{c}}{\~o}es, j{\'a} que elas podem ser
processadas {\`a} medida que s{\~a}o coletadas. O modelo
din{\^a}mico inclui perturba{\c{c}}{\~o}es devido ao
geopotencial e as observa{\c{c}}{\~o}es s{\~a}o as
solu{\c{c}}{\~o}es de navega{\c{c}}{\~a}o, obtidas de um
receptor GPS a bordo do sat{\'e}lite, composta de
posi{\c{c}}{\~a}o e tend{\^e}ncia do rel{\'o}gio de receptor.
As componentes de velocidade da solu{\c{c}}{\~a}o de
navega{\c{c}}{\~a}o n{\~a}o s{\~a}o utilizadas devido {\`a}
sua baixa precis{\~a}o. Simula{\c{c}}{\~o}es e testes s{\~a}o
feitos utilizando dados reais do sat{\'e}lite TOPEX/POSEIDON e
observa{\c{c}}{\~o}es compreendendo tr{\^e}s dias. O vetor de
estado estimado {\'e} comparado com as efem{\'e}rides precisas
POE (Precise Orbit Ephemeris), produzidas pelo JPL/NASA. O
desempenho e caracter{\'{\i}}sticas do procedimento proposto,
tais como o efeito do modelo din{\^a}mico, tamanho do passo de
integra{\c{c}}{\~a}o e efeito da disponibilidade seletiva (SA),
s{\~a}o analisados para mostrar o impacto em termos da
precis{\~a}o global alcan{\c{c}}ada. ABSTRACT: The Global
Positioning System (GPS) is a satellite navigation system that
allows the users to determine 3D positioning and the time with
high precision. Its main purposes are: aid to radionavigation in
three dimensions with high precision positioning, navigation in
real time, global coverage and quick acquisition of data sent by
the GPS satellites. It is proposed, in this work, to estimate, in
real time, an orbital state vector composed by position, velocity,
bias and drift of the GPS receiver clock on board satellites by
processing the raw navigation solution obtained by the on-board
receiver. In this work the Kalman filter is used to estimate the
state vector based on the incoming observations from the receiver.
The Kalman filter is used due to its robustness in real time
applications, without unnecessary storage of observations, as they
can be processed while being collected. The filter dynamic model
includes perturbation due to geopotential and the observations are
the raw navigation solution composed of position and receiver
clock bias. The velocity components of the navigation solution are
not used due to its low accuracy. Simulations and tests are done
using real data from TOPEX/POSEIDON satellite and comprising three
days of observations. A comparison is done between the estimated
state vector and the precise orbit ephemeris (POE) produced by
JPL/NASA. The proposed procedure performance and characteristics
are analyzed, including effects of the dynamic model, step-size of
integration and SA (Selective Availability) effect, to show the
impact on the procedure in terms of global accuracy obtained.",
committee = "Prado, Antonio Fernando Bertachini de Almeida (presidente) and
Kuga, H{\'e}lio Koiti (orientador) and Chiaradia, Ana Paula
Marins (orientadora) and Moraes, Rodolpho Vilhena de and Orlando,
Valcir and M{\^o}nico, Jo{\~a}o Francisco Galera",
copyholder = "SID/SCD",
englishtitle = "Orbit determination of artificial satellites in real time using
gps navigation solution",
language = "pt",
pages = "123",
ibi = "6qtX3pFwXQZ3P8SECKy/CMhKD",
url = "http://urlib.net/ibi/6qtX3pFwXQZ3P8SECKy/CMhKD",
targetfile = "publicacao.pdf",
urlaccessdate = "26 jul. 2024"
}