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Application of Deep Learning in Deep Space Wireless Signal Identification for Intelligent Channel SensingKabir, Md Faisal January 2020 (has links)
No description available.
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5G@15 GHz Testbed Development and EvaluationHabib, Imran January 2018 (has links)
Due to the advancement in technology and the increase in the amount of data beingtransferred through wireless channels, many developments in the techniques and speedof data transfer have been observed in the past few decades. The current trend incellular technology is transforming from 4G to 5G. So, to meet future requirements,it is highly necessary to have further improvements in technology like modulationtechniques, Channel access methods, etc. Many top research institutes around the worldare investing heavily in research and development of 5G.Radio waves have been used for a very long time in mobile phone communication,but providers are experimenting with broadcasting on millimeter waves which usehigher frequencies ranging from 6GHz to 300GHz. Data characteristics like power,SNR, interference, etc. need to be evaluated for these high frequencies. As 5G is still ininitial phases of development, there are not many testing tools to check and evaluateits performance. A testbed is a testing tool which is used for conducting rigorous,transparent, and replicable testing, experimenting and evaluating the performance ofthese propagated data at these high frequencies.The thesis work evaluates the implementation structures of the 5G testbed @15GHzand its performance in indoor and outdoor scenarios. It also talks about the methods ofsignal generation through Matlab and it’s transmission at 15GHz using Xilinx FPGAand Analog devices’ FMCOMMS5 transceiver. This data is then transmitted andreceived by patch antennas provided by Ericsson AB. Various techniques were used inorder to improve the signal, like using RF hardware components and software modules.Different channel sounding techniques were used in order to achieve the synchronizationbetween the transmitter and the receiver node in order to measure the properties ofthe channel. All of the experiments were performed by implementing a single-inputsingle-output system (SISO) module of the 5G testbed. This SISO system can be easilytransformed into a multiple-input-multiple-output system (MIMO) by replicating theoriginal SISO system.The result shares some interesting findings on the readiness of the 5G testbed for aiiiivbetter understanding of the future technology. It is concluded that this testbed providessomewhat a reliable platform to test the performance of the 5G technology. / Tack vare teknikutveckling och ökning i mängden data som sänds trådlöst, hardatatakterna ökat enormt under de senaste decennierna. Den senaste trended inomtrådlös kommunikationärövergången från 4G till 5G. För att möte framtida krav,finns det därför behov av ytterligare teknologiutveckling, t ex i modulationstekniker och kanalaccessmetoder. Många forskningsinstitut runt om i världen investerar därför i forskning och utveckling av 5G.Radiovågor har använts under väldigt lång tid för mobil kommunikation, men tillverkare och operatörer experimenterar med sändningar i millimetervågsområdet, som använder högre frekvenser i området från 6GHz till 300GHz. Egenskaper såsom effektdämpning, SNR, interferens, osv, behöver utvärderas för dessa högre frekvenser. Eftersom utvecklingen av 5G fortfarande är i en tidig fas, finns inte så många testverktygtillgängliga för prestandautvärdering. En testbädd är ett testverktyg som användsför att utföra rigorös, transparent och upprepningsbar testning, experimentering och prestandautvärdering av data som har sänts vid dessa höga frekvenser.Denna rapport utvärderar implementationsstrukturer för en 5G-testbädd vid 15GHz,och dess prestanda i inomoch utomhusscenarier. Den beskriver även metoder försignalgenerering via Matlab och sändning vid 15GHz mha Xilinx FPGA och Analog devices’ FMCOMMS5 radiomoduler. Signalen sänds sedan via patch-antenner från Ericsson AB. Olika metoder användes för att förbättra signalen, både med radiofrekvens hårdvara och mjukvarumoduler. Olika kanalmätningsmetoder har använts för att nå synkronisering mellan sändaroch mottagarnoderna, för att mäta kanalegenskaper. Alla experimenten utfördes genom att implementera en SISO-modul (en sändarresp. mottagarantenn) av 5G-testbädden. Detta SISO-system kan enkelt utökas till ett MIMO system (flera sändaroch mottagarantenner) genom att replikera SISO-systemet.Resultaten visar att 5G-testbädden är redo att användas för att nå bättre förståelse av framtida teknologin. Slutsatsen är att testbädden erbjuder en tämligen påliglig plattformför att utvärdera prestanda för 5G-teknologi.
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Vision-based Testbeds For Control System ApplicaitonsSivilli, Robert 01 January 2012 (has links)
In the field of control systems, testbeds are a pivotal step in the validation and improvement of new algorithms for different applications. They provide a safe, controlled environment typically having a significantly lower cost of failure than the final application. Vision systems provide nonintrusive methods of measurement that can be easily implemented for various setups and applications. This work presents methods for modeling, removing distortion, calibrating, and rectifying single and two camera systems, as well as, two very different applications of vision-based control system testbeds: deflection control of shape memory polymers and trajectory planning for mobile robots. First, a testbed for the modeling and control of shape memory polymers (SMP) is designed. Red-green-blue (RGB) thresholding is used to assist in the webcam-based, 3D reconstruction of points of interest. A PID based controller is designed and shown to work with SMP samples, while state space models were identified from step input responses. Models were used to develop a linear quadratic regulator that is shown to work in simulation. Also, a simple to use graphical interface is designed for fast and simple testing of a series of samples. Second a robot testbed is designed to test new trajectory planning algorithms. A templatebased predictive search algorithm is investigated to process the images obtained through a lowcost webcam vision system, which is used to monitor the testbed environment. Also a userfriendly graphical interface is developed such that the functionalities of the webcam, robots, and optimizations are automated. The testbeds are used to demonstrate a wavefront-enhanced, Bspline augmented virtual motion camouflage algorithm for single or multiple robots to navigate through an obstacle dense and changing environment, while considering inter-vehicle conflicts, iv obstacle avoidance, nonlinear dynamics, and different constraints. In addition, it is expected that this testbed can be used to test different vehicle motion planning and control algorithms.
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Scalable Cognitive Radio Network Testbed in Real TimeYu, Kevin Z 01 June 2021 (has links) (PDF)
Modern society places an increasingly high demand on data transmission. Much of that data transmission takes place through communication over the frequency spectrum. The channels on the spectrum are limited resources. Researchers realize that at certain times of day some channels are overloaded, while others are not being fully utilized. A spectrum management system may be beneficial to remedy this efficiency issue. One of the proposed systems, Cognitive Radio Network (CRN), has progressed over the years thanks to studies on a wide range of subjects, including geolocation, data throughput rate, and channel handoff selection algorithm, which provide fundamental support for the spectrum management system. To move CRN technology forward, in this thesis we propose a physical, scalable testbed for some of the extant CRN methodologies. This testbed integrates IEEE standards, FCC guidelines, and other TV band regulations to emulate CRN in real time. With careful component selections, we include sufficient operational functionalities in the system, while at the same time making sure it remains affordable. We evaluate the technical feasibility of the testbed by studying several simple CRN logics. When comparing a system with a selection table implemented to those with naive selection methods, there is more than a 60 percent improvement in the overall performance.
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A MULTI-FIDELITY MODELING AND EXPERIMENTAL TESTBED FOR TESTING & EVALUATION OF LEARNING-BASED SYSTEMSAtharva Mahesh Sonanis (17123428) 10 October 2023 (has links)
<p dir="ltr">Learning-based systems (LBS) have become essential in various domains, necessitating the development of testing and evaluation (T&E) procedures specifically tailored to address the unique characteristics and challenges of LBS. However, existing frameworks designed for traditional systems do not adequately capture the intricacies of LBS, including their evolving nature, complexity, and susceptibility to adversarial actions. This study advocates for a paradigm shift in T&E, proposing its integration throughout the entire life cycle of LBS, starting from the early stages of development and extending to operations and sustainment. The research objectives focus on exploring innovative approaches for designing LBS-specific T&E strategies, creating an experimental testbed with multi-fidelity modeling capabilities, investigating the optimal degree of test and evaluation required for LBS, and examining the impact of system knowledge access and the delicate balance between T&E activities and data/model rights. These objectives aim to overcome the challenges associated with LBS and contribute to the development of effective testing approaches that assess their capabilities and limitations throughout the life cycle. The proposed experimental testbed will provide a versatile environment for comprehensive testing and evaluation, enabling researchers and practitioners to assess LBS performance across varying levels of complexity. The findings from this study will contribute the development of efficient testing strategies and practical approaches that strike a balance between thorough evaluation and data/model rights. Ultimately, the integration of continuous T&E insights throughout the life cycle of LBS aims to enhance the effectiveness and efficiency of capability delivery by enabling adjustments and improvements at each stage.</p>
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Vehicle detection and tracking using wireless sensors and video camerasBandarupalli, Sowmya 06 August 2009 (has links)
This thesis presents the development of a surveillance testbed using wireless sensors and video cameras for vehicle detection and tracking. The experimental study includes testbed design and discusses some of the implementation issues in using wireless sensors and video cameras for a practical application. A group of sensor devices equipped with light sensors are used to detect and localize the position of moving vehicle. Background subtraction method is used to detect the moving vehicle from the video sequences. Vehicle centroid is calculated in each frame. A non-linear minimization method is used to estimate the perspective transformation which project 3D points to 2D image points. Vehicle location estimates from three cameras are fused to form a single trajectory representing the vehicle motion. Experimental results using both sensors and cameras are presented. Average error between vehicle location estimates from the cameras and the wireless sensors is around 0.5ft.
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Método para avaliação de sistema de gerenciamento de redes orientado a eficiência energética. / Method for evaluating network management systems oriented to energy efficiency.Januário, Guilherme Carvalho 12 February 2014 (has links)
Funcionalidades de eficiência energética vêm sendo integradas a protocolos e sistemas de gerenciamento de redes. Várias dessas funcionalidades afetam a rede de diferentes modos, acarretando compromissos. Podem afetar a confiabilidade e a disponibilidade da rede ao colocarem equipamentos e enlaces em modo dormente; e podem afetar o tempo de vida dos equipamentos ao alterarem seu modo de utilização. Os resultados da integração dessas funcionalidades à rede podem ser avaliados por emulação, que provê informação sobre como algum mecanismo de roteamento em particular, fruto dessa integração, agiria em diferentes condições de rede. Preparar um ambiente de experimentação que trate das interações entre diferentes funções da rede, considerando as funcionalidades de eficiência energética, traz alguns desafios. Uma combinação de emulação e implementação das principais funcionalidades de eficiência energética provê uma visão mais próxima sobre o que pode ocorrer em implantações reais de sistemas de gerenciamento energeticamente eficiente. Esta dissertação discute (i) como se avaliarem os compromissos existentes no emprego de técnicas de eficiência energética, mostrando também como o tempo de vida de equipamentos pode ser alterado e como a confiabilidade e disponibilidade da rede podem ser degradadas, e discute (ii) requisitos para o desenvolvimento de um ambiente de experimentação para avaliação de tais técnicas. O ambiente é baseado em roteadores implementados por software, para emulação de funcionalidades ainda não disponíveis, mas desejadas, de equipamentos de rede. Após a experimentação do protótipo de um sistema de gerenciamento de redes orientado por política de eficiência energética, aplicam-se os métodos de avaliação dos compromissos ocasionados por este sistema. / Energy efficiency features are being integrated in network protocols and management systems. Many of such features affect the network in different ways, thus yielding tradeoffs. They can affect the reliability and availability of the network when they put devices or links into sleep mode, and they can affect the lifetime of the devices as a result of the new operating pattern. The effects of integrating these features to the network can be assessed through emulation, which can provide insight on how a particular routing mechanism would perform in different network conditions. In addition, building an experimentation environment that is able to comprehensively account for interactions between different network functions taking into account energy efficiency features is challenging. A combination of emulation and implementation of major energy efficiency features provides a view closer to what may happen in a real deployment of energy-efficient management systems. This dissertation discusses (i) how to evaluate the tradeoffs existing between the use of energy-efficiency techniques and the lifetime of devices and with the reliability and availability of the network, and (ii) requirements for the development of a testbed to evaluate such techniques. The testbed is based on software routers, so to emulate future and desired network equipment functionalities. After experiments with the prototype of a sustainability-oriented network management system based on policies, an evaluation about the tradeoffs brought by such system to the network is performed.
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A Multi-tier fog architecture for vídeo on demand streaming / Uma arquitetura de névoa multicamada para streaming de vídeo sob demandaSANTOS, Hugo Leonardo Melo dos 05 March 2018 (has links)
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Previous issue date: 2018-03-05 / Os usuários estão mudando seus hábitos de comunicação tradicional com base
em chamadas de voz ou mensagens de texto para serviços de vídeo em tempo real ou sob
demanda consumidos em dispositivos móveis. Nesse sentido, a transmissão de conteúdo de
vídeo considerando uma Qualidade de Experência (QoE) adequada nas infraestruturas de
redes sem fio móvel é um problema crítico nas comunidades acadêmicas e industriais. Além
disso, o vídeo sob demanda tem um consumo crescente na Internet, exigindo maior largura
de banda e menor latência. Neste contexto, um paradigma de computação em névoa pode
ser aplicado para melhorar a experiência do usuário em redes sem fio. A computação
em névoa pode melhorar a QoE para transmissão de vídeo sob demanda, tanto fazendo
cache de vídeo quanto fazendo adaptação de conteúdo na borda da rede. No entanto, é
importante avaliar o desempenho do download de vídeos com diferentes configurações de
codec e em cache mais próximo do usuário para medir o ganho sob perspectiva do usuário.
Projetamos uma arquitetura de computação em névoa de várias camadas com 3 níveis
localizados na nuvem, um perto da borda e outra nos dispositivos m´oveis. Avaliamos o
desempenho do download do vídeo de vários níveis localizados em aplicações geográficas
distintas para aplicações multimídia. N´os avaliamos em um ambiente experimental com
rede livre e congestionada de vídeos transmitidos codificados em H.264 e H.265 com 3
taxas de bits em um cenário implantado no testbed FIBRE. Nós coletamos métricas de
QoE, tempo de inicial para reprodução, tempo de congelamento, métricas de QoS, tempo
de viagem ida e volta do pacote e consumo de energia para analisar os ganhos para cada
configuração de vídeo. Esses resultados mostraram uma compreensão importante do uso
de cache , codec e taxa de bits em cenários de redes multimídia. / Users are changing their traditional communication paradigm based on voice calls
or text messages to real-time or on demand video services consumed on mobile devices. In
this sense, the transmission of video content considering an adequate Quality of Experience
(QoE) in mobile wireless networking infrastructures is a critical issue in both academic and
industrial communities. Furthermore, video on demand have a growing consumption over
Internet requiring higher bandwidth and lower latency. In this context, a fog computing
paradigm can enhance the user experience in wireless networks. Fog computing for video
on demand streaming can improve QoE by both video caching and adaptation schemes.
However, it is important to evaluate the performance of downloading the videos with
different codec configuration and cached closer to the user to measure the gain from
the user perspective. We designed a multi-tier fog computing architecture with three
levels located in the cloud, nearer the edge and in mobile devices. We evaluated the
performance of downloading the video from multiple tier located in distinct geographical
with a multimedia application. We assessed in an experimental environment with idle and
congested network of streamed videos coded into H.264 and H.265 with three bitrates in a
scenario deployed in the FIBRE testbed. We collected QoE metrics, playback start time,
freeze times, QoS metric, round-time trip, and energy consumption to analyze the gains
for each video configuration. These results showed an important understanding about
cache, codec and bitrate schemes in multimedia networking scenarios.
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Método para avaliação de sistema de gerenciamento de redes orientado a eficiência energética. / Method for evaluating network management systems oriented to energy efficiency.Guilherme Carvalho Januário 12 February 2014 (has links)
Funcionalidades de eficiência energética vêm sendo integradas a protocolos e sistemas de gerenciamento de redes. Várias dessas funcionalidades afetam a rede de diferentes modos, acarretando compromissos. Podem afetar a confiabilidade e a disponibilidade da rede ao colocarem equipamentos e enlaces em modo dormente; e podem afetar o tempo de vida dos equipamentos ao alterarem seu modo de utilização. Os resultados da integração dessas funcionalidades à rede podem ser avaliados por emulação, que provê informação sobre como algum mecanismo de roteamento em particular, fruto dessa integração, agiria em diferentes condições de rede. Preparar um ambiente de experimentação que trate das interações entre diferentes funções da rede, considerando as funcionalidades de eficiência energética, traz alguns desafios. Uma combinação de emulação e implementação das principais funcionalidades de eficiência energética provê uma visão mais próxima sobre o que pode ocorrer em implantações reais de sistemas de gerenciamento energeticamente eficiente. Esta dissertação discute (i) como se avaliarem os compromissos existentes no emprego de técnicas de eficiência energética, mostrando também como o tempo de vida de equipamentos pode ser alterado e como a confiabilidade e disponibilidade da rede podem ser degradadas, e discute (ii) requisitos para o desenvolvimento de um ambiente de experimentação para avaliação de tais técnicas. O ambiente é baseado em roteadores implementados por software, para emulação de funcionalidades ainda não disponíveis, mas desejadas, de equipamentos de rede. Após a experimentação do protótipo de um sistema de gerenciamento de redes orientado por política de eficiência energética, aplicam-se os métodos de avaliação dos compromissos ocasionados por este sistema. / Energy efficiency features are being integrated in network protocols and management systems. Many of such features affect the network in different ways, thus yielding tradeoffs. They can affect the reliability and availability of the network when they put devices or links into sleep mode, and they can affect the lifetime of the devices as a result of the new operating pattern. The effects of integrating these features to the network can be assessed through emulation, which can provide insight on how a particular routing mechanism would perform in different network conditions. In addition, building an experimentation environment that is able to comprehensively account for interactions between different network functions taking into account energy efficiency features is challenging. A combination of emulation and implementation of major energy efficiency features provides a view closer to what may happen in a real deployment of energy-efficient management systems. This dissertation discusses (i) how to evaluate the tradeoffs existing between the use of energy-efficiency techniques and the lifetime of devices and with the reliability and availability of the network, and (ii) requirements for the development of a testbed to evaluate such techniques. The testbed is based on software routers, so to emulate future and desired network equipment functionalities. After experiments with the prototype of a sustainability-oriented network management system based on policies, an evaluation about the tradeoffs brought by such system to the network is performed.
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On MIMO Systems and Adaptive Arrays for Wireless Communication : Analysis and Practical AspectsWennström, Mattias January 2002 (has links)
<p>This thesis is concerned with the use of multiple antenna elements in wireless communication over frequency non-selective radio channels. Both measurement results and theoretical analysis are presented. New transmit strategies are derived and compared to existing transmit strategies, such as beamforming and space-time block coding (STBC). It is found that the best transmission algorithm is largely dependent on the channel characteristics, such as the number of transmit and receive antennas and the existence of a line of sight component. Rayleigh fading multiple input multiple output (MIMO) channels are studied using an eigenvalue analysis and exact expressions for the bit error rates and outage capacities for beamforming and STBC is found. In general are MIMO fading channels correlated and there exists a mutual coupling between antenna elements. These findings are supported by indoor MIMO measurements. It is found that the mutual coupling can, in some scenarios, increase the outage capacity. An adaptive antenna testbed is used to obtain measurement results for the single input multiple output (SIMO) channel. The results are analyzed and design guidelines are obtained for how a beamformer implemented in hardware shall be constructed. The effects of nonlinear transmit amplifiers in array antennas are also analyzed, and it is shown that an array reduces the effective intermodulation distortion (IMD) transmitted by the array antenna by a spatial filtering of the IMD. A novel frequency allocation algorithm is proposed that reduces IMD even further. The use of a low cost antenna with switchable directional properties, the switched parasitic antenna, is studied in a MIMO context and compared to array techniques. It is found that it has comparable performance, at a fraction of the cost for an array antenna.</p>
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