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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Development of position sensor using phase-based continuous wave radar

Chuckpaiwong, Ittichote 08 1900 (has links)
No description available.
22

Radar multiple beamforming simulation including noise and tolerance effects

Manrique, Gonzalo A. January 1981 (has links)
Thesis (M.S.)--Ohio University, November, 1981. / Title from PDF t.p.
23

Life cycle analysis of a radar system /

Reynolds, Obie D. January 1993 (has links)
Report (M.S.)--Virginia Polytechnic Institute and State University. M.S. 1993. / Abstract. Includes bibliographical references (leaf 64). Also available via the Internet.
24

Implementation of a low-cost FM-CW radar /

Hoole, Jonathan G. January 2008 (has links)
Thesis (MScIng)--University of Stellenbosch, 2008. / Bibliography. Also available via the Internet.
25

Skupina RADAR / The RADAR Group

Tučková, Kateřina January 2014 (has links)
THESIS ABSTRACT The thesis named The Radar Group deals with one of the creative groups that entered the Czech artistic scene after 1956, after the 20th Congress of the Soviet Communist Party (SCP) in February 1956, when the establishment of minor associations within the Union of Czechoslovak Artists was allowed. The Radar Group announced its foundation in 1960 and presented its first independent exhibition in 1961. It introduced eighteen members, of whom the most significant authors from the ranks of the defunct Group 42 (Skupina 42) - František Gross, František Hudeček a Ladislav Zívr - belonged to the established artists of previous generation. The majority of younger members born between 1923 and 1930 introduced their painting, sculptural and graphical works at the exhibition mostly for the first time. The members of the Radar Group may be regarded as the representatives of so- called "tame modern art" who took up to the pre-war modernism in the loosening period of the late 1950's. Their status within the contemporary scene was very high as they were coming out of the positions shielded by the Union - most were the Union members, some even functionaries in the Union senior management. This is the reason why the group did not become a part of the opposing Block of Art Groups (Blok tvůrčích skupin), though...
26

Estimação de fase absoluta e de linha de base em radar interferométrico de abertura sintética com múltiplas antenas / Absolute phase and baseline estimation for interferometric synthetic aperture radar using multiple antennas

Bins, Leonardo Sant'Anna, 1961 02 June 2014 (has links)
Orientador: Max Henrique Machado Costa / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-24T13:29:51Z (GMT). No. of bitstreams: 1 Bins_LeonardoSant'Anna_D.pdf: 7799361 bytes, checksum: 9e2474fa080f4e6f30dd2971af9cd670 (MD5) Previous issue date: 2014 / Resumo: Dois problemas importantes na interferometria SAR (Synthetic Aperture Radar) são a estimação da fase absoluta e das linhas de base. O conhecimento preciso da fase absoluta e das linhas de base são fundamentais para a geração de modelos digitais de superfície ou terreno com alta precisão planimétrica e altimétrica. A estimação de fase absoluta consiste de duas etapas. A primeira etapa efetua o desdobramento da fase, o qual recupera a fase absoluta com os correspondentes múltiplos de 2?. A segunda etapa consiste na estimação do deslocamento de fase, causada pela combinação de erros de sincronização no sistema de aquisição de dados com erros de processamento da Interferometria SAR (InSAR). A estimação de linha de base consiste na determinação da posição da antena escrava relativa à posição da antena mestre (ou antena de referência). As contribuições desta tese consistem na concepção e na implementação de três métodos que se valem de múltiplas antenas (múltiplos interferogramas) para resolver esses dois problemas, como se segue. O primeiro método efetua o método de desdobramento de fase pontual, através do desdobramento de fase iterativo dos interferogramas, seguido da fusão dos mesmos, usando máxima verossimilhança. O segundo método refina a estimação de fase absoluta através da estimação do deslocamento de fase usando múltiplas antenas não colineares. O método se baseia na minimização da distorção geométrica (ou erro relativo) induzida pelo processamento com a presença de deslocamentos de fase com valores diferentes do verdadeiro. Uma das vantagens do método é que ele dispensa a instalação de refletores de canto na região imageada. Por último, um algoritmo do tipo Monte Carlo foi desenvolvido para a determinação das posições relativas das antenas escravas em relação à antena mestre. O método utiliza refletores de canto, cujas posições em campo são conhecidas, para reduzir o erro quadrático médio / Abstract: Two important issues in SAR interferometry (InSAR) are absolute phase and baseline estimation. The precise knowledge of these parameters is essential for the production of digital elevation models with high accuracy. The absolute phase estimation can be done in two steps. The first step performs the unwrapping of the phase, which retrieves the 2? multiples of the phase. The second step estimates the phase offset caused by a combination of errors in the acquisition system and in SAR interferometry (InSAR) processing. The baseline estimation determines the relative position of the slave antenna with respect to the master antenna (reference antenna). The contributions of this thesis consist in the design and implementation of three methods that use multiple antennas to address the above issues. The first method performs the unwrapping of the phase in a pixel based fashion, by iteratively unfolding the phase corresponding to each interferograma, followed by maximum likelihood fusion of the unwrapped phases. The second method refines the absolute phase estimation of the first step by incorporating a phase offset estimation based on multiple, noncollinear, antennas. This is achieved by minimizing the geometrical distortion (relative error) in the reconstructed digital elevation model induced by erroneous phase offsets in the interferograms. One advantage of this method is that it does not require the deployment of corner reflector in the area to be imaged. Lastly, the third method deals with baselines estimation. A baseline is determined by the relative positions of the slave and master antennas. The estimation is performed with a greedy stochastic algorithm of Monte Carlo type which uses corner reflectors with precisely known positions. A new position for the slave antenna is accepted when the mean square error of the corner reflector positions is reduced / Doutorado / Telecomunicações e Telemática / Doutor em Engenharia Elétrica
27

Medium frequency radar studies of meteors

Grant, Stephen Ian. January 2003 (has links)
Thesis (Ph.D.)--University of Adelaide, School of Chemistry and Physics, 2003? / "July 2003." Includes bibliographical references (leaves 459-484). Also available in a print form.
28

Measurement correlation in a target tracking system using range and bearing observations /

Pistorius, Morné. January 2006 (has links)
Thesis (MSc)--University of Stellenbosch, 2006. / Bibliography. Also available via the Internet.
29

Application of Ground Penetrating Radar to the Detection of Subsurface Cavities

Kuhns, Gary L. 01 October 1983 (has links) (PDF)
Ground Penetrating Radar (GPR) identifies subsurface features by distinguishing materials with different dielectric constants and electrical conductivities. Subsurface cavities can, therefore, be detected by the variation in their electrical properties from the electrical properties of the surrounding material. To test the cavity detection ability of GPR, subsurface cavities of varying size, shape and content were modeled. Radar response to the cavity models was found to be affected by the composition of the surrounding soil material, the depth of the groundwater table, and the radar signal frequency. Based on knowledge gained from the cavity modeling study, a natural subsurface cavity was identified during a GPR field investigation. Limestone features such as bedding planes and fractures were mapped, and a detailed lake bottom profile was obtained by the radar system.
30

Texture analysis in sonar images

Dunlop, Jonathan January 1999 (has links)
No description available.

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