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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.
1

Equalization techniques for multipath mitigation in aeronautical telemetry /

Paje, Vladimir Ignacio, January 2005 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Electrical and Computer Engineering, 2005. / Includes bibliographical references (leaves 53-54).
2

Data management of flight test telemetry frames /

Samaan, Mouna M. January 1998 (has links)
Thesis (PhD)--University of South Australia, 1998
3

Space-time coding with offset modulations /

Nelson, N. Thomas, January 2007 (has links) (PDF)
Thesis (Ph. D.)--Brigham Young University. Dept. of Electrical and Computer Engineering, 2007. / Includes bibliographical references (p. 137-143).
4

A PAM decomposition of weak CPM /

Wardle, Mason B., January 2005 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Electrical and Computer Engineering, 2005. / Includes bibliographical references (p. 67-70).
5

Prototype MIMO Transmitter for Spin Stabilized Vehicles

Eckler, Kyle 10 1900 (has links)
ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / This paper describes the design of an inexpensive and scalable transmitter for a Multiple-Input Multiple-Output (MIMO) communication system. The transmitter is intended to be used in aerospace applications, especially in spin stabilized vehicles. A field programmable gate array (FPGA) in the modulator will implement a modified Alamouti space time block code which will take advantage of the cyclostationary nature of the channel to increase the system data rate.
6

Physical layer design of a robust low-power low-complexity optical wireless sensor system with angular diversity for metal-enclosed environments /

Trullinger, Von. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2005. / Printout. Includes bibliographical references (leaves 91-93). Also available on the World Wide Web.
7

Frequency-domain equalization for continuous phase modulation

Saleem, Sajid 13 January 2014 (has links)
Continuous phase modulation~(CPM) is a non-linear, constant-envelope modulation scheme with memory, known for its bandwidth and power efficiency. Multi-h CPM uses multiple modulation indices in successive symbol intervals to improve the error performance as compared to single-h CPM~(basic CPM that utilizes only a single modulation index). One of the major applications of multi-h CPM is in aeronautical telemetry systems. Modern aeronautical devices host an increasing number of sensors, which can transmit flight testing data to the ground station. However, this excess data transfer increases the intersymbol interference, and thus channel equalization is required at the receiver. The objective of our research is to propose low-complexity frqeuency-domain equalization~(FDE) techniques for multi-h CPM waveforms. For a modulation scheme with memory, such as CPM, the cyclic constraint on the FDE block necessitates the use of an extra segment of symbols, called intrafix or tail segment. We have used very simple geometric arguments to derive upper and lower bounds on the length of the intrafix in terms of the parameters of the modulation scheme and the Frobenius number. It is concluded that the length of the intrafix for multi-h CPM schemes is typically shorter than those required for single-h modulation schemes. We propose two receiver architectures; one uses a matched filter front end, while the other utilizes a fractional sampling front end. Various simplifications are proposed for each architecture, and the trade-off between receiver complexity and performance is analyzed and verified through detailed simulation studies.
8

Satellite-based web server

Maluleke, Enock Vongani 12 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: There is a large variety of telemetry recervmg software currently available for the reception of telemetry information from different satellites. Most of the software used in receiving telemetry data is satellite specific. Hence, a user-friendly way is needed to make telemetry data easily accessible. A satellite-based web server is aimed at providing telemetry information to any standard web browser as a way of bringing space technology awareness to the people. Two different satellite-based web server methods are examined in this thesis. Based on the evaluation, the on-board File server with proxy server was proposed for satellite-based web server development. This requires that the File server be ported to the on-board computer of the satellite. The web proxy server is placed on the ground segment with the necessary communication requirements to communicate with the on-board File server. In the absence of satellite, the satellite-based web server was successfully implemented on two computers, laying a good foundation for implementation on the on-board computer of the satellite (OBe). / AFRIKAANSE OPSOMMING: Daar is 'n groot verskeidenheid telemetrie ontvangs sagteware huidiglik beskikbaar vir die ontvangs van telemetrie informasie vanaf verskillende satelliete. Die meeste van die sagteware wat gebruik word om telemetrie data te ontvang is satelliet spesifiek. Gevolglik, 'n gebruikers vriendelike metode is nodig om telemetrie data maklik beskikbaar te maak. 'n Satelliet-gebaseerde web-bediener word beoog om telemetrie informasie te verskaf aan enige standaard web-blaaier as 'n metode om mense bewus te maak van ruimte tegnologie. Twee verskillende satelliet gebaseerde web-bediener metodes salondersoek word in hierdie tesis. Gebaseer op 'n evaluering, word die aanboord leêr-bediener met instaanbediener voorgestel vir satelliet-gebaseerde webbediener ontwikkeling. Hiervoor is dit nodig dat die leêr-bediener na die aanboord rekenaar van die satelliet gepoort word. Die web instaanbediener word op die grond segment geplaas met die nodige kommunikasie benodighede, om te kommunikeer met die aanboord leêr-bediener. In die afwesigheid van die satelliet was die satellietgebaseerde web-bediener met sukses geïmplementeer op twee rekenaars, met die gevolg dat 'n goeie fondasie gelê is vir die implementering op die aanboord rekenaar van die satelliet (OBC).
9

Estimation de la vitesse des courants marins à partir de séquences d'images satellitaires / Oceanic currents estimation from satellite image sequences

Beyou, Sébastien 12 July 2013 (has links)
Cette thèse étudie des méthodes d'assimilation de données par filtrage particulaire à l'estimation d'écoulements fluides observés au travers de séquences d'images. Nous nous appuyons sur un filtre particulaire spécifique dont la distribution de proposition est donnée par un filtre de Kalman d'ensemble, nommé filtre de Kalman d'ensemble pondéré. Deux variations à celui-ci sont introduites et étudiées. La première consiste à utiliser un bruit dynamique (permettant de modéliser l'incertitude du modèle et de séparer les particules entre elles) dont la forme spatiale suit une loi de puissance, cohérente avec la théorie phénoménologique de la turbulence. La deuxième variation repose sur un schéma d'assimilation multi-échelles introduisant un mécanisme de raffinements successifs à partir d'observations à des échelles de plus en plus petites. Ces deux méthodes ont été testées sur des séquences synthétiques et expérimentales d'écoulements 2D incompressibles. Ces résultats montrent un gain important sur l'erreur quadratique moyenne. Elles ont ensuite été testées sur des séquences d'images satellite réelles. Sur les images réelles, une bonne cohérence temporelle est observée, ainsi qu'un bon suivi des structures de vortex. L'assimilation multi-échelles montre un gain visible sur le nombre d'échelles reconstruites. Quelques variations additionnelles sont aussi présentées et testées afin de s'affranchir de problèmes importants rencontrés dans un contexte satellitaire réel. Il s'agit notamment de la prise en compte de données manquantes sur les images de température de surface de l'océan. En dernier lieu, une expérience d'un filtre de Kalman d'ensemble pondéré avec un modèle océanique complet est présentée pour une assimilation de champs de courants de surface en mer d'Iroise, à l'embouchure de la Manche. Quelques autres pistes d'amélioration sont également esquissées et testées. / This thesis studies fluid flows estimation with particle filtering-based assimilation methods imaged using digital cameras. We rely on a specific particle filter, of which the proposal distribution is given by an Ensemble Kalman Filter, namely the Weighted Ensemble Kalman Filter. Two variations of this method are introduced and tested. The first consists in using a dynamical noise (which modelizes the model uncertainty and separates the particles from each others); its spatial form obeys to a power law stemming from the phenomenological theory of the turbulence. The second variation relies on a multiscale assimilation scheme introduicing successive refinements from observations at smaller and smaller scales. These two methods are tested on synthetic and experimental sequences of 2D incompressible flows. Results show an important gain on the Root Mean Square Error. They are then tested on real satellite images. A good temporal coherence and a good tracking of vortex structures are observed on the real images. The multiscale assimilation shows a visible gain on the number of reconstructed scales. Some additional variations are also presented and tested in order to take into account important problems in a real satellite context. The main contribution is the management of missing data areas in the Sea Surface Temperature sequence. Lastly an experiment involving a Weighted Ensemble Kalman Filter with a complete oceanic model is presented for a surface currents fields assimilation in Iroise Sea near the English Channel mouth. Some other improvements are also drawn and tested.

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