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Adaptive equalization and capacity analysis for amplify-and-forward relays : a thesis submitted in fulfillment of the requirements for the degree of Doctor of Philosophy in Electrical and Electronic Engineering, University of Canterbury, Christchurch, New Zealand /Firag, Abdulla. January 1900 (has links)
Thesis (Ph. D.)--University of Canterbury, 2008. / Typescript (photocopy). "December 2008." Includes bibliographical references (p. 165-174). Also available via the World Wide Web.
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[en] SIMULATION OF EQUATORIAL AND LOW-LATITUDE IONOSPHERIC EFFECTS ON THE GROUND-BASED AUGMENTATION SYSTEM (GBAS) / [pt] SIMULAÇÃO DOS EFEITOS DA IONOSFERA EQUATORIAL E DE BAIXAS LATITUDES NO SISTEMA DE AUMENTO BASEADO NO SOLO (GBAS)TEDDY MODESTO SURCO ESPEJO 14 December 2020 (has links)
[pt] Esta tese apresenta um estudo dos efeitos ionosféricos em um Sistema de
Aumento Baseado no Solo (GBAS) em regiões equatorial e de baixas latitudes. A
ionosfera afeta a propagação dos sinais de GPS e pode reduzir a precisão do
posicionamento nas regiões equatorial e de baixas latitudes. Sistemas auxiliares
foram desenvolvidos para atender aos requisitos de segurança da aviação. Nesse
contexto, o GBAS fornece maior precisão para correções diferenciais. Para avaliar
o desempenho de um GBAS, um modelo de simulação do sinal-no-espaço GPS
L1 foi desenvolvido, considerando o retardo ionosférico baseado nas distribuições
estatísticas dos resíduos de Conteúdo Eletrônico Total vertical obtido do modelo
IRI e estimativas da Rede Brasileira de Monitoramento Contínuo, em combinação
com representação para a cintilação ionosférica de amplitude, simulada com base
em distribuições de probabilidade (Alfa) - (Mi), bem como a cintilação de fase, gerada de
acordo com as relações empíricas entre os índices (s)4 and (Sigma)(Fi). O modelo de sinal
do GPS L1 também considera erros de relógios e aleatórios, retardos
troposféricos, ambigüidade de ciclo e efeitos de multipercurso, para uma
descrição completa. Os resultados de sinal-no-espaço são injetados em um modelo
de simulação da instalação terrestre do GBAS, implementado para detectar uma
variedade de possíveis anomalias ou falhas no sinal-no-espaço e para gerar
correções diferenciais baseadas em algoritmos de monitoramento. O GBAS gera
correções e seu desempenho é avaliado para aproximações de aeronaves em
diferentes condições ionosféricas nos aeroportos do Rio de Janeiro e Fortaleza,
enfatizando a Categoria de aproximação I. Os erros horizontais e verticais são
estimados usando correções de GBAS para avaliar a precisão. A integridade do
GBAS também é analisada calculando os níveis de proteção horizontal e vertical. / [en] This research presents a study on ionospheric effects on a Ground Based
Augmentation System (GBAS) in equatorial and low latitude regions. The
ionosphere affects the propagation of GPS signals and can reduce the positioning
accuracy in the equatorial and low-latitude regions. Auxiliary systems have been
developed to meet the safety requirements of aviation. In this context, GBAS
provide higher accuracy for differential corrections. To evaluate the performance
of a GBAS, a simulation model of the GPS L1 signal-in-space has been
developed, considering ionospheric delay based on statistical distributions of
vertical Total Electron Content residuals obtained from IRI model and Rede
Brasileira de Monitoramento Contínuo estimates, in combination with amplitude
ionospheric scintillation simulated based on (Alfa) - (Mi) probability distributions, as well
as phase scintillation, generated according to empirical relationships between the
indices (S)4 and (Sigma)(Fi). The GPS L1 signal model also considers clock and random
errors, tropospheric delays, ambiguity, and multipath, for a complete description.
The signal in space results are injected into a GBAS ground facility simulation
model, implemented to detect a varied array of possible anomalies or failures in
the signal in space and to generate differential corrections based on monitoring
algorithms. The GBAS generates corrections and its performance is evaluated for
aircraft approaches under different ionospheric conditions at the Rio de Janeiro
and Fortaleza Airports, emphasizing Approach Category I. The horizontal and
vertical errors are estimated using GBAS corrections to evaluate the accuracy.
The GBAS integrity is also analyzed by computing the horizontal and vertical
protection levels.
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Výkonnost služby GNSS pro aplikace prostorové navigace civilního letectví v ČR / The Performance of GNSS Services for the Area Navigation Applications of Civil Aviation in CRPtáček, Pavel January 2014 (has links)
The dissertation deals with the assessment of navigation performance of GPS/EGNOS system in user position domain. Examination is based on a static signal in space monitoring and evaluation campaign to assess the ability to provide sufficient performance for new navigation procedures. GPS/EGNOS system is the first primary navigation system to be used in the airspace of Czech Republic. The first part describes the benefits of using new procedures, summarizes navigation development and current status. The second part defines components of GPS/EGNOS primary navigation system being analysed and its characteristics with the potential impact on the quality of approach navigation services to be provided and ensured by EGNOS. Subsequently, the methodology for critical evaluation of GPS/EGNOS signal in space navigation performance in position domain to be monitored by of air traffic services was formulated, using new methods for investigation of accuracy, integrity and continuity with the focus on final approach procedures. Simultaneously supporting software for data analysis against performance requirements in position domain was designed. Based on campaigns of static experimental measurements and detailed analysis of combined GPS/EGNOS performance against the demands, the level of performance is analysed, the findings are presented and conclusions are made. In the last part, the usage of permanent geodetic stations for regular evaluation of GNSS performance for civil aviation purposes is designed and verified, and the conclusions based on navigation performance evaluation of observations from all selected station in the Czech Republic.
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