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421	Performance of In-Band Full-Duplex for 5G Wireless Networks Al-Saadeh, Osama January 2016 (has links) In-band full duplex is a new duplexing scheme that allows radio nodes to transmit and receive, utilizing the same frequency and time resources. The implementation of in-band full duplex was not feasible in practice, due to the effect of self-interference. But then, advances in signal processing made it possible to reduce this effect. However, the system level performance of in-band full duplex has not been investigated thoroughly.Through computer simulations, we investigate the performance of in-band full duplex, for indoor 5G small cell wireless networks. We examine the performance of in-band full duplex in comparison to dynamic and static time division duplexing. Additionally, we analyze the performance of the duplexing schemes with two interference mitigation techniques, namely beamforming and interference cancellation.Our results indicate that for highly utilized wireless networks, in-band full duplex should be combined with beamforming and interference cancellation, in order to achieve a performance gain over traditional duplexing schemes. Only then, in-band full duplex is considered advantageous, at any network utilization, and any downlink to uplink traffic demand proportion. Our results also suggest that in order to achieve a performance gain with in-band full duplex in both links, the transmit power of the access points should be comparable to the transmit power of the mobile stations. / Inomband hel duplex är en ny typ av duplexmetod som tillåter radionoder att sända och ta emot i samma frekvensoch tidsresurs. Att implementera inomband hel duplex har fram tills nu inte ansetts praktiskt genomförbart till följd av självstörningar. Framsteg inom signalbehandling har dock gjort det möjligt att begränsa denna självstörningseffekt. Emellertid har systemprestanda av inomband hel duplex inte undersökts tillräckligt noga i tidigare verk.Inomband hel duplex och dess prestanda för trådlösa 5G småcellsnätverk inomhus har studerats med hjälp av datasimuleringar och jämförts med dynamisk och statisk tidsdelning. Utöver detta har prestanda för de olika duplexmetoderna med avseende på två tekniker för störningsundertryckning, lobformning och störningseliminering, också undersökts.Våra resultat indikerar att för trådlösa nätverk med högt radioresursutnyttjande bör inomband hel duplex kombineras med lobformning och störningseliminering för att uppnå en prestandavinst jämfört med traditionella duplexmetoder. Bara då kan inomband hel duplex anses vara fördelaktig oberoende av radioresursutnyttjande och andelen upp- och nedlänkstrafik.Resultaten tyder också på att sändareffekten för radioaccesspunkterna bör vara jamförbar med den för mobilenheterna för att en prestandavinst med inomband hel duplex ska kunna uppnås. / Wireless networks, In-band full duplex, Static-time division duplexing, Dynamic-time division duplexing, Interference mitigation techniques, small cell, 5G, mmWave bands, Beamforming, Interference cancellation. Wireless networks In-band full duplex Static-time division duplexing Dynamic-time division duplexing Interference mitigation techniques small cell 5G mmWave bands Beamforming Interference cancellation. Trådlösa nätverk Inomband hel duplex Statisk tidsdelning Dynamisk tidsdelning Störningsundertryckningsmetoder Små celler 5G Millimetervågsfrekvenser Lobformning Störningseliminering. Telecommunications Telekommunikation
422	Mikrofonní pole malých rozměrů pro odhad směru přicházejícího zvuku / Small-Size Microphone Array for Estimation of Direction of Arrival of Sound Kubišta, Ladislav January 2020 (has links) This thesis describe detection of direction receiving sound with small–size microphone array. Work is based on analyzing methods of time delay estimation, energy decay or phase difference signal. Work focus mainly on finding of angle of arrival in small time difference. Results of measuring, as programming sound, so sound recorded in laboratory conditions and real enviroment, are mentioned in conclusion. All calculations were done by platform Matlab
423	Reconnaissance Radar Robot Holm, Kasper, Henrysson, Erik January 2023 (has links) During the last century, various countries' armed forces have used unmanned aerial vehicles, commonly known as drones. In recent years, strives have been made to develop small commercial drones that have allowed the general public to afford and use them for recreational purposes. The availability of drones has led to immoral applications of the technology. Such applications need to be faced with anti-measures and effective detection methods. Therefore, this thesis aims to develop a mobile reconnaissance robot that can detect commercial drones with radar. It describes integrating radar sensors with single-board computers to detect and localise air-bound objects. The finished product aims to be used for educational and exhibition purposes at the Swedish Armed Forces technical school to increase awareness of the technology. / <p>Försvarsmaktens tekniska skola i Halmstad var intressenter för uppsatsen.</p> radar signal processing signal processing state machine state machine test testing radar testing radar technology frequency modulated continuous wave fmcw pulse radar raspberry pi single board computer sbc poe power over ethernet mqtt mqtt package python drones uav unmanned aerial vehicle drone detection radar robot swedish armed forces swedish armed forces technical school fmts beamforming fast fourier transform fft point cloud point clustering software design Computer and Information Sciences Data- och informationsvetenskap Computer Sciences Datavetenskap (datalogi) Software Engineering Programvaruteknik Signal Processing Signalbehandling Computer Systems Datorsystem
424	Emploi de techniques de traitement de signal MIMO pour des applications dédiées réseaux de capteurs sans fil / Adaptive optimisation of MIMO Channel for Smart sensor networks Ben Zid, Maha 09 July 2012 (has links) Dans ce travail de thèse, on s'intéresse é l'emploi de techniques de traitement de signal de systèmes de communication MIMO (Multiple Input Multiple Output) pour des applications aux réseaux de capteurs sans fil. Les contraintes énergétiques de cette classe de réseau font appel à des topologies particulières et le réseau peut être perçu comme étant un ensemble de grappes de nœuds capteurs. Ceci ouvre la porte à des techniques avancées de communication de type MIMO. Dans un premier temps, les différents aspects caractérisant les réseaux de capteurs sans fil sont introduits. Puis, les efforts engagés pour optimiser la conservation de l'énergie dans ces réseaux sont résumés. Les concepts de base de systèmes MIMOs sont abordés dans le deuxième chapitre et l'exploration par voie numérique de différentes pistes de la technologie MIMO sont exposées. Nous nous intéressons à des techniques de diversité de polarisation dans le cadre de milieux de communication riches en diffuseurs. Par la suite, des méthodes de type beamforming sont proposées pour la localisation dans les réseaux de capteurs sans fil. Le nouvel algorithme de localisation est présenté et les performances sont évaluées. Nous identifions la configuration pour la communication inter-grappes qui permet pour les meilleurs compromis entre énergie et efficacité spectrale dans les réseaux de capteurs sans fil. Finalement, nous envisageons la technique de sélection de nœuds capteurs afin de réduire la consommation de l'énergie dans le réseau de capteur sans fil. / The aim of this work is to study from a signal processing point of view the use of MIMO (Multiple Input Multiple Output) communication systems for algorithms dedicated to wireless sensor networks. We investigate energy-constrained wireless sensor networks and we focus on cluster topology of the network. This topology permits for the use of MIMO communication system model. First, we review different aspects that characterize the wireless sensor network. Then, we introduce the existing strategies for energy conservation in the network. The basic concepts of MIMO systems are presented in the second chapter and numerical results are provided for evaluating the performances of MIMO techniques. Of particular interest, polarization diversity over rich scattering environment is studied. Thereafter, beamforming approach is proposed for the development of an original localization algorithm in wireless sensor network. The novel algorithm is described and performances are evaluated by simulation. We determine the optimal system configuration between a pair of clusters that permits for the highest capacity to energy ratio in the fourth chapter. The final chapter is devoted to sensor nodes selection in wireless sensor network. The aim of using such technique is to make energy conservation in the network. Réseaux de capteurs sans fil MIMO Clustering Diversité de polarisation Capacité Énergie Localisation Beamforming Technique de sélection MIMO Clustering Polarization diversity Capacity Energy Localization Beamforming Selection technique

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