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Approved for public release; distribution is unlimited / This thesis is devoted to analyzing the problem of masking a reflected radar signal, in order to degrade the radar receiver's performance. This is to be accomplished by appropriately choosing the Power Spectral Density (PSD) of a power constrained colored noise interference to be generated either by the target itself or by pre-positioned "friendly" noise makers. The goal in either case is to generate interference signals that result in decreased receiver probability of detection, P(D), for a given receiver probability of false alarm, P(F). Efforts to identify appropriate PSD's of the power constrained interference were carried out by evaluating the receivers' P(D) as a function of P(F) for two specific target models. The performance results for the various receivers investigated demonstrate that the noise interference generated by the noise makers can achieve significant levels of degradation, while the target generated noise interference tends to improve rather than degrade the radar receiver's performance. In all cases considered, the sine squared shaped noise interference PSD is more effective at degrading the receiver performance than any other kind of PSD analyzed. / http://archive.org/details/performanceofrad00mavr / Captain, Hellenic Army

L'analyse de la Polarimétrie SAR pour la détection des structures archéologiques de surface et de subsurface du site de Gebel Barkal (Sudan), inscrit dans la Liste du Patrimoine Mondial depuis 2003, est l'objectif des travaux de recherche effectués dans le cadre de cette thèse de doctorat. En particulier, les capacités de pénétration dans le sol des bandes C et L ont été analysées grâce à l'utilisation des images des capteurs ALOS PALSAR (archivées) et RADARSAT-2 (spécifiquement acquises). En outre, l'activité de recherche illustre les potentialités de l'intégration des données satellitaires polSAR et optiques dans un projet SIG dédié, réalisé grâce à une collaboration avec les Universités de Turin et de Venise (Italie). La surveillance des sites archéologiques au moyen des images satellitaires polSAR représente un avantage considérable pour la recherche archéologique, alors que les anomalies détectées peuvent concerner les opérations de fouille ou être vérifiées au sol, comme démontré dans ce manuscrit, ou encore elles peuvent contribuer à la réalisation des plans d'intervention pour les sites archéologiques en péril. / Aim of PhD research is to exploit SAR Polarimetry technique for the identification of surface and subsurface archaeological features in the site of Gebel Barkal (Sudan), inscribed in the UNESCO World Heritage List since 2003. Sand penetration capability of both C-band and L-band sensors are discussed analysing archived ALOS PALSAR and RADARSAT-2 specifically acquired (2012-2013) images. Moreover, the research activity illustrates the potential of integrating SAR polarimetric and optical satellite data in a dedicated GIS project, realised in collaboration with the Universities of Turin and Venice (Italy). The monitoring of ancient sites by means of remotely acquired polarimetric SAR data represents a benefit for the archaeological research, where detected anomalies can address archaeological excavations or ground truth verification, as shown in the PhD dissertation, and where threatening factors affect the integrity of a cultural site.

Cette recherche a pour objectif d'étudier l'impact des micro-ondes sur des structures archéologiques toujours visibles de l'ancienne cité de Samarra, la capitale de l'ancien Abbasside Califat situé en Iraq. Trois zones ont été sélectionnées pour cette recherche Doctorale : une cité octogonale, trois champs de courses et la cité de al-Mutawakkiliyya. Les menaces à lesquelles le site est exposé et son importance historique ont permis d'inscrire la cité sur la liste UNESCO des sites en danger (2007). Cela a donné une raison de plus pour enquêter sur cette zone au moyen des capteurs SAR RADARSAT-2 et ALOS PALSAR. Le potentiel de l'imagerie SAR, en fait, est bien connu, en particulier pour les régions du Monde où des enquêtes in situ ne sont pas autorisées en raison de l'instabilité politique (comme dans le cas de Samarra) et en raison de la possibilité d'acquérir quelque soit la couverture nuageuse et dans tout genre d'illumination (jour / nuit). / This work has as goal to study the microwaves behavior over the archaeological structures still visible in the historical city of Samarra, the capital of the ancient Abbasid Caliphate located in Iraq. Three areas were taken into account for the Ph.D. research: an octagonal city, three racecourses stadiums and the city of al-Mutawakkiliyya. Threats to which the site is exposed and its historical importance let the city to be inscribed in the list of UNESCO sites in danger (2007). This gave a reason more to investigate this area by means of SAR RADARSAT-2 and ALOS PALSAR satellites. SAR potentiality, in fact, is well known, in particular for those areas of the World where surveys in situ are not allowed because of political instability (as in the case of Samarra) and because of the possibility of acquiring with any cloud cover conditions and in any kind of illumination (day/night).

Orientador: Maurício Galo / Banca: Daniel Rodrigues dos Santos / Banca: Edson Aparecido Mitishita / Banca: Aluir Porfírio Dal Poz / Banca: Antonio Maria Garcia Tommaselli / Resumo: Esta tese trata da extração e regularização automática de contornos de telhados de edificações obtidos a partir de dados LiDAR (Light Detection and Ranging) adquiridos por sistema de varredura a LASER (Light Amplification by Stimulated Emission of Radiation) aerotransportado. Em linhas gerais, dois problemas são tratados. O primeiro corresponde à determinação adaptativa do parâmetro α do algoritmo alpha-shape, utilizado na obtenção do contorno aproximado, a partir da nuvem de pontos. O segundo refere-se à regularização/modelagem dos contornos de edificações no espaço tridimensional, incluindo edificações formadas por segmentos curvos de maior complexidade. Com relação ao primeiro problema, duas abordagens foram propostas, ambas baseadas no espaçamento médio entre os pontos. A principal contribuição das abordagens propostas está ligada à determinação adaptativa de α, possibilitando minimizar a influência da variação da densidade de pontos. Para solucionar o problema ligado a regularização de contornos, uma metodologia baseada no conceito de CD-Spline (Changeable Degree Spline) foi desenvolvida. A principal contribuição do uso da CD-Spline está ligada à habilidade de modelar contornos formados por segmentos com diferentes níveis de complexidade no espaço n-dimensional, sendo esses modelados por funções polinomiais de diferentes graus. Na metodologia proposta, a função polinomial que melhor modela cada segmento é selecionada de forma automática por meio da análise estatística do... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This Doctoral dissertation deals with the automatic extraction and regularization of building roof boundaries from LiDAR (Light Detection and Ranging) data, obtained by airborne LASER (Light Amplification by Stimulated Emission of Radiation) scanning. In this context, two problems were explored. The first corresponds to the adaptive determination of the parameter α of the alpha-shape algorithm, used to extract the approximate contour, from the available point cloud. The second refers to the regularization/modeling of building boundaries in the three-dimensional space, including buildings formed by curved segments of high complexity. Regarding the first problem, two approaches were proposed, both based on average point spacing. The main contribution of the approaches is related to the adaptive determination of α, allowing to minimize the influence of the point density variation. In order to solve the problem related to boundary regularization, a method based on the concept of CD-Spline (Changeable Degree Spline) was developed. The CD-Spline has ability to model boundaries formed by segments with different levels of complexity in n-dimensional space, which are modeled by polynomial functions of different degrees. In order to select the polynomial function automatically, an iterative approach of the CD-Spline was proposed. In this methodology, the polynomial function that best models each segment is selected by means of the statistical analysis of the residuals in each iteration... (Complete abstract click electronic access below) / Doutor

A project report submitted to the Faculty of Engineering, University of the Witwatersrand, in partial fulfilment of the requirements for the degree of Master of Science in Engineering. Johannesburg, April 1994. / This project report describes the development of a high speed data acquisition and processing system (DAPS) for an experimental monopulse tracking radar at the Division of Manufacturing and Aeronautical Systems Technology (Aerotek), of CSIR. The system development involved replacement of existing data acquisition hardware and software with an enhanced, PC based, integrated high speed data acquisition system. The system is used for radar acceptance testing, radar monitoring during trials and capture of large volumes of data for off-line processing to pursue research into the phenomenology of radar cross section. The work performed during the execution of this project represents an effort in three technology areas. These are Digital hardware design of custom interface hardware for the ISA bus as implemented on most PC's. This was not a major aim of the project, but was required in the absence of suitable hardware. Formal software specification and design using the real time extensions of Hatley and Pirbhai to the Yourdon and de Marco data flow analysis methodology. The existing software had not been designed using any formal method, and suffered a lack of documentation throughout all phases of the development. The way this project was undertaken has served as an exercise in following the approach, which resulted in a product which is better documented and more maintainable. There are elements of total quality management that are still missing though. • Quality management during software development. At the time of commencement of the project there was no formal commitment to software quality management at Aerotek. Commitment to IS09000 accreditation in future has required that a solid quality ethic and management system be instituted. Current software development follows this approach. A discussion of the topic appears in the conclusion. The DAPS has been in use for approximately two years now. With continued minor modification to meet new user requirements, it has successfully enhanced the usability of the radar system during trials and measurements with the SAAF. / MT2017

O Pantanal é uma área mundialmente conhecida por ser uma das maiores planícies com alagamentos sazonais do mundo. Do ponto de vista de seus sistemas deposicionais, é uma área importante na caracterização de sistemas fluviais distributivos, característicos de áreas subsidentes e com grande relevância na interpretação do registro estratigráfico de sistemas fluviais em bacias sedimentares. Entretanto, os aspectos temporais da evolução dos sistemas fluviais do Pantanal são ainda pouco investigados, sendo ainda mais escassos os estudos com abordagem de investigações de sua subsuperfície. Como forma de contribuir para a compreensão da evolução temporal dos sistemas fluviais na região, o presente estudo apresenta os resultados de levantamentos de Radar de Penetração do Solo (GPR - Ground Penetrating Radar) e interpretação de radar fácies no Megaleque do Rio Taquari, no lobo meandrante do rio de mesmo nome, no Pantanal. Como resultado, após o processamento das informações coletadas, foram selecionadas nove seções GPR representativas do sistema, nas quais foram identificadas três radar fácies. Através da interpretação destas, foi possível identificar geometrias deposicionais em profundidades distintas do padrão formado pelos sistemas atuais, interpretadas como um sistema entrelaçado possivelmente de maior vazão que o atual e que implicam em transformações no sistema fluvial do rio Taquari no Quaternário, possivelmente devido a mudanças climáticas. / The Pantanal is internationally recognized as one of the largest seasonally flooded areas in the world. From a depositional systems point of view, it is important in the characterization of distributive fluvial systems, typical of subsiding areas and bearing great relevance for the interpretation of the fluvial rock record preserved within sedimentary basins. Despite that, the temporal aspects of the evolution of the fluvial systems in Pantanal are still poorly investigated, and studies based on subsurface surveys are even more scarce. As a means to contribute for the understanding of the fluvial systems evolution in the region, this dissertation presents the results of Ground Penetrating Radar (GPR ) surveys and radar facies interpretation in the Taquari river megafan, specifically in the meandering lobe of the homonymous river in the Pantanal. After data processing, nine GPR sections representative of the system were selected, in which three radar facies were identified. Their interpretation lead to the identification of subsurface depositional geometries which are distinct from the modern day patterns, interpreted as a braided system possibly with greater discharge than the modern meandering river. This implies in changes in the Taquari fluvial system in the Quaternary, probably due to climate change.

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This thesis describes research performed into the segmentation and classification of features on images of wound terrain generated from an airborne millimetre wave radar. The principles of operation of the radar are established and it is shown how an image is produced from this particular radar. The parameters such as wavelength, antenna size and pulse length are related to the images and a mathematical description of the radar data is given. The effectiveness of established image processing techniques is reviewed when applied to millimetre wave radar images and a statistical classification technique is seen to yield encouraging results. This method of segmentation and classification is then extended to make optimal use of the available information from the radar. An orthogonal expansion of the Poincaré sphere representation of polarised radiation is established and it is shown how different terrain types cluster in the eigenspace of these spherical harmonics. Segmentation then follows from the clustering properties of pixels within this multidimensional eigenspace and classification from the locations of the clusters.