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Even if 3rd and 4th generation wireless systems aim to achieve multimedia services at high speed, it is rather difficult to have full-fledged multimedia services due to insufficient capacity of the systems. There are many technical challenges placed on us in order to realize the real multimedia services. One of those challenges is how efficiently to allocate resources to traffic as the wireless systems evolve. The review of the literature shows that strategic manipulation of traffic can lead to an efficient use of resources in both wire-line and wireless networks. This aspect brings our attention to the role of link layer protocols, which is to orchestrate the transmission of packets in an efficient way using given resources. Therefore, the Media Access Control (MAC) layer plays a very important role in this context. In this research, we investigate technical challenges involving resource control and management in the design of MAC protocols based on the characteristics of traffic, and provide some strategies to solve those challenges. The first and foremost matter in wireless MAC protocol research is to choose the type of multiple access schemes. Each scheme has advantages and disadvantages. We choose Wireless Code Division Multiple Access/Time Division Duplexing (WCDMA/TDD) systems since they are known to be efficient for bursty traffic. Most existing MAC protocols developed for WCDMA/TDD systems are interested in the performance of a unidirectional link, in particular in the uplink, assuming that the number of slots for each link is fixed a priori. That ignores the dynamic aspect of TDD systems. We believe that adaptive dynamic slot allocation can bring further benefits in terms of efficient resource management. Meanwhile, this adaptive slot allocation issue has been dealt with from a completely different angle. Related research works are focused on the adaptive slot allocation to minimize inter-cell interference under multi-cell environments. We believe that these two issues need to be handled together in order to enhance the performance of MAC protocols, and thus embark upon a study on the adaptive dynamic slot allocation for the MAC protocol. This research starts from the examination of key factors that affect the adaptive allocation strategy. Through the review of the literature, we conclude that traffic characterization can be an essential component for this research to achieve efficient resource control and management. So we identify appropriate traffic characteristics and metrics. The volume and burstiness of traffic are chosen as the characteristics for our adaptive dynamic slot allocation. Based on this examination, we propose four major adaptive dynamic slot allocation strategies: (i) a strategy based on the estimation of burstiness of traffic, (ii) a strategy based on the estimation of volume and burstiness of traffic, (iii) a strategy based on the parameter estimation of a distribution of traffic, and (iv) a strategy based on the exploitation of physical layer information. The first method estimates the burstiness in both links and assigns the number of slots for each link according to a ratio of these two estimates. The second method estimates the burstiness and volume of traffic in both links and assigns the number of slots for each link according to a ratio of weighted volumes in each link, where the weights are driven by the estimated burstiness in each link. For the estimation of burstiness, we propose a new burstiness measure that is based on a ratio between peak and median volume of traffic. This burstiness measure requires the determination of an observation window, with which the median and the peak are measured. We propose a dynamic method for the selection of the observation window, making use of statistical characteristics of traffic: Autocorrelation Function (ACF) and Partial ACF (PACF). For the third method, we develop several estimators to estimate the parameters of a traffic distribution and suggest two new slot allocation methods based on the estimated parameters. The last method exploits physical layer information as another way of allocating slot to enhance the performance of the system. The performance of our proposed strategies is evaluated in various scenarios. Major simulations are categorized as: simulation on data traffic, simulation on combined voice and data traffic, simulation on real trace data. The performance of each strategy is evaluated in terms of throughput and packet drop ratio. In addition, we consider the frequency of slot changes to assess the performance in terms of control overhead. We expect that this research work will add to the state of the knowledge in the field of link-layer protocol research for WCDMA/TDD systems. / Ph. D.

Yes / Reconfigurable antennas play important roles in smart and adaptive systems and are the subject of many research studies. They offer several advantages such as multifunctional capabilities, minimized volume requirements, low front-end processing efforts with no need for a filtering element, good isolation, and sufficient out-ofband rejection; these make them well suited for use in wireless applications such as fourth generation (4G) and fifth generation (5G) mobile terminals. With the use of active materials such as microelectromechanical systems (MEMS), varactor or p-i-n (PIN) diodes, an antenna’s characteristics can be changed through altering the current flow on the antenna structure. If an antenna is to be reconfigurable into many different states, it needs to have an adequate number of active elements. However, a large number of high-quality active elements increases cost, and necessitates complex biasing networks and control circuitry. We review some recently proposed reconfigurable antenna designs suitable for use in wireless communications such as cognitiveratio (CR), multiple-input multiple-output (MIMO), ultra-wideband (UWB), and 4G/5G mobile terminals. Several examples of antennas with different reconfigurability functions are analyzed and their performances are compared. Characteristics and fundamental properties of reconfigurable antennas with single and multiple reconfigurability modes are investigated. / European Union’s Horizon 2020 research and innovation programme under grant agreement H2020-MSCA-ITN-2016 SECRET-722424.

Yes / Fourth generation systems require the use of both amplitude and phase modulation to efficiently utilize the available spectrum and to obtain high data rates, hence imposing stringent requirements on the power amplifier in terms of efficiency and linearity and requires the power amplifier to operate linearly and efficiently. The B3G base station transceiver Doherty power amplifier was designed to operate over the frequency range of 3.47GHz to 3.53GHz mobile WiMAX band using Freescale¿s N-Channel Enhancement-Mode Lateral MOSFET Transistor, MRF7S38010HR3; The performances of the Doherty amplifier are compared with that of the conventional Class AB amplifier. The results of 43 dBm output power and 66% power added efficiency are achieved.

Made available in DSpace on 2016-03-15T19:37:56Z (GMT). No. of bitstreams: 1 BRUNO FERRAZ IZARIO.pdf: 4620887 bytes, checksum: bd842cabfdadb0bcb55e0ea548c9fba5 (MD5) Previous issue date: 2015-08-28 / The Long Term Evolution (LTE) system belongs to the 4th generation phone system. It is standardized by 3GPP and utilizes several technologies to improve the performance of data transmission. This permits flexibility for mobile devices, which enables a high data rate in the range of 50 Mbps to 100 Mbps, and admit access to various multimedia services. The study presents the results of deploying an LTE network in the city of Campinas, São Paulo, Brazil, using the 700 MHz band by comparing it to the 2.5 GHz band. By calculating the budget for the LTE system link is information as possible to highlight throughput and cell coverage radius, and other information. The Radio Mobile software was used for verification of results. / O sistema Long Term Evolution (LTE) pertence ao sistema da 4ª geração de telefonia (4G). Ele é padronizado pelo 3GPP e utiliza diversas tecnologias para melhorar o desempenho de transmissão de dados. O mesmo permite uma flexibilidade para dispositivos móveis, possibilitando uma alta taxa de dados na faixa de 50 Mbps a 100 Mbps, além de admitir acesso a diversos serviços multimídias. O estudo apresenta resultados de implantação de uma rede LTE na cidade de Campinas, São Paulo, Brasil, utilizando a faixa de 700 MHz comparando-a com a faixa de 2,5 GHz. Através do cálculo de link budget para o sistema LTE, é possível destacar informações como throughput e raio da célula de cobertura, além de outras informações. O software radio mobile foi utilizado para fins de comprovação de resultados.

La croissance exponentielle du nombre de dispositifs communicants et des services sans fils émergents fixe des objectifs toujours plus haut pour répondre à la demande de capacité sans cesse croissante des utilisateurs. Cela pose des défis constants pour atteindre les objectifs envisagés. La réutilisation spectrale élevée (High efficiency spectral reuse) a été adopté, cependant, elle conduit à des interférences accrues sur le réseau, ce qui dégrade les performances. L'OFDM (Orthogonal Frequency Division Multiplexing) est utilisé comme solution dans les réseaux de 4 G. Grâce à son orthogonalité, l'OFDM élimine l'interférence intra-cellulaire, mais l'interférence inter-cellule reste importante. Plusieurs méthodes connues sous le nom d'Inter-Cell interférences coordination (ICIC) ont été proposées pour les diminuer. L'ICIC permet la gestion des ressources radio coordonnée entre plusieurs cellules appelées ENodeB. Ces eNodeB peuvent partager les informations nécessaires grâce à l'interface X2 qui les relient, ces informations sont transmises par des messages LTE normalisés. Lorsque les ENodeBs sélectionnent égoïstement les ressources, la théorie de jeux non-coopératifs est largement appliquée pour trouver un juste équilibre. Dans cette thèse, nous mettons l'accent sur l'ICIC pour la liaison descendante d'un système OFDMA cellulaire dans le contexte du projet SOAPS (Spectrum opportuniste accès à la Sécurité publique). Ce projet a pour but l'amélioration de la planification des ressources de fréquences pour fournir des services à large bande dans les systèmes PMR (radiocommunications mobiles privées) en utilisant les technologies LTE. Nous adressons le problème d'ICIC en proposant quatre solutions différentes sous forme d'algorithmes entièrement décentralisés, ces algorithmes se basent sur la théorie des jeux non-coopératifs avec des équilibres de Nash purs des jeux considérés / The exponential growth in the number of communications devices has set out new ambitious targets to meet the ever-increasing demand for user capacity in emerging wireless systems. However, the inherent impairments of communication channels in cellular systems pose constant challenges to meet the envisioned targets. High spectral reuse efficiency was adopted as a solution to higher data rates. Despite its benefits, high spectral reuse leads to increased interference over the network, which degrades performances of mobile users with bad channel quality. To face this added interfence, OFDM (Orthogonal Frequency Division Multiplexing) is used for the new 4th generation network. Thanks to its orthogonality OFDM eliminates the intra-cellular interference, but when the same resources are used in two adjacents cells, the inter-cell interference becomes severe. To get rid of the latter, several methods for Inter-Cell Interference Coordination (ICIC) have been proposed. ICIC allows coordinated radio resources management between multiple cells. The eNodeBs can share resource usage information and interference levels over the X2 interface through LTE-normalized messages. Non-cooperative game theory was largely applied were eNodeBs selfishly selects resource blocks (RBs) in order to minimize interference. In this thesis, we stress on ICIC for the downlink of a cellular OFDMA system in the context of the SOAPS (Spectrum Opportunistic Access in Public Safety) project. This project focuses on the improvement of frequency resource scheduling for Broadband Services provision by PMR (Private Mobile Radio) systems using LTE technologies. We addressed this problem with four different solutions based on Non-cooperative game theory, three algorithms are devoted to RB selection in order to manage the interference, while the last one is a power control scheme with power economy and enhanced system performances

This thesis is about using airborne laser scanning data for making maps for Orienteering. In this thesis were used altimetry data DMR 4G and DMR 5G. These data are provided by ČUZK. The control measuring was made in choosen area to verify the accuracy. In this thesis is described procedure of data collection and their treatment. The results of this thesis are two illustrations of the orienteering maps.

Recent studies have shown that there are currently more than 1.08 billion of Smartphones in the world, with around 89% of them used throughout the day. On average each of these users transfers more than 450 Mbytes per month via either a cellular network or a Wi-Fi network. So far it has been up to the user to decide which one of these two networks to use at each particular moment. In this master’s thesis, the potential energy savings that could be achieved by means of automating the choice of network interface are explored. This way, the user equipment itself would be able to initiate handovers from one radio access technology to another depending on each particular service and on the environmental conditions, and hence it could extend its battery life. The work has focused in energy efficient vertical handovers (VHOs) between Long-Term Evolution (LTE) and Wi-Fi networks. The rapid growth and increasing interest in LTE networks have been the main reasons why these networks have been chosen over Third Generation Mobile Networks. Nevertheless this work can be easily extended to other radio access technologies such as WiMAX (Worldwide Interoperability for Microwave Access) or UMTS (Universal Mobile Telecommunication System). During the thesis project, the potential energy savings via VHOs depending on the type of service have been studied, as well as the different processes involved in a handover decision process. In order to do so, an energy consumption profile of each interface has been built, the different services have been modeled, and a heterogeneous scenario with Wi-Fi and LTE networks has been simulated. The thesis presents how these savings change within each service and with the environmental conditions (network load, interferences). The results show that large energy savings can be achieved. Nevertheless, the potential savings for each different user device can significantly differ. The VHO decision process includes two main aspects that need further study: investigating energy efficient ways of discovering accessible Wi-Fi access points and measuring the available throughput in each network at the moment of the decision. In addition, within LTE-Advanced and HetNets (Heterogeneous Networks), a lot of research regarding how LTE operators can offload traffic to smaller networks is being performed. These smaller networks consist basically of LTE micro cells and Wi-Fi. Both the energy savings and the potential energy expenses of offloading different kinds of traffic to a Wi-Fi network were also studied in this master’s thesis project, using the same approach described in the previous two paragraphs. / Enligt beräkningar så finns det nu mer än 1.08 miljarder smarta telefoner i världen, och ungefär 89% av dem används varje dag. Varje användare överför mer än 450 megabyte per månad i genomsnitt, antingen via cellulära mobilnät eller Wi-Fi. För närvarande är det användaren som avgör vilket av dessa interface som ska användas vid varje tidpunkt. I detta examensarbete utvärderas vilka energibesparingar som kan uppnås genom att automatisera valet av nätverksinterface. På detta vis skulle den mobila enheten själv utföra handover från en radioaccessteknik till en annan beroende på aktiva tjänster och på radioomgivningen, och därmed utöka batteriets livstid. Detta examensarbete fokuserar på vertikal handover mellan LTE och Wi-Fi nätverk. Den snabba tillväxten och det ökande intresset för LTE är den främsta anledningen till att LTE har valts istället för 3G. Det är dock möjligt att med små förändringar generalisera arbetet till andra radioaccesstekniker, till exempel WiMAX eller UMTS. De potentiella energibesparingarna genom vertikala handovers för olika typer av tjänster har studerats, liksom de olika stegen i handover-beslutsprocessen. För detta syfte har en energikonsumtionsprofil skapats för varje interface, de olika tjänsterna har modellerats och ett scenario med Wi-Fi- och LTE-nätverk har simulerats. Denna rapport beskriver hur dessa energibesparingar ändras för varje tjänstetyp och med ändringar av omgivningen (nätverkslast och interferens). Resultaten har visat att stora energibesparingar kan uppnås, även om dessa besparingar kan variera mycket för olika UEs. Beslutet om vertikal handover inkluderar två huvudsakliga aspekter som kräver fortsatta studier: energieffektiva metoder för att upptäcka tillgängliga WiFi-accesspunkter som går att ansluta sig till och mätning av den upplevda datahastigheten i varje nätverk före beslutet om vertikal handover tas. Parallelt med detta examensarbete pågår omfattande studier om hur mobiloperatörer kan avlasta datatrafik till basstationer med kortare räckvidd. Dessa småskaliga nätverk förväntas bestå av LTE mikro/pico celler och/eller Wi-Fi nätverk. Detta examensarbete inkluderar även studier av de potentiella energibesparingar eller energikostnader för att avlasta olika slags trafik till Wi-Fi nätverk.

Ce travail présente deux contributions clés dans le domaine des réseaux de communication sans fil 4G+/5G, en particulier dans le domaine de la détection MIMO d’ordre supérieur et le design (conception) de réseau relai semi-duplex. La première partie de ce travail de recherche s’intéresse au développement d’une stratégie de détection MIMO d’ordre supérieur pour les terminaux 4G+/5G existants et futurs, d’un point de vue à la fois théorique et pratique. Une nouvelle technique de décomposition QR Bloc de prétraitement est proposée pour un récepteur LTE dans un scénario limité à un seul utilisateur, interférence limitée, ainsi qu’un scénario point par point dont les résultats surlignent les avantages et inconvénients en performance et complexité. La deuxième partie de cette étude comprend une étude de faisabilité d’une stratégie de message novatrice à deux phases et trois parties pour un réseau relai semi-duplex à couche physique, qui comporte un codage de superposition et un décodage d’annulation d’interférence successif, conscient des interférences. Un point clé de cette étude était d’analyser la performance du schéma d’adaptation des liaisons proposées dans le régime non asymptotique et d’évaluer l’efficacité spectrale (ES) par rapport aux hypothèses théoriques des blocs d’asymptotiquement grandes longueurs. Une comparaison ES supplémentaire est également présentée, avec une transmission de relais à deux étapes non coopérative et une stratégie de transmission point à point. Les résultats obtenus révèlent les gains d'ES qui peuvent être obtenus en exploitant la coopération de couche physique entre le relais et la station de base. / The evolution of wireless communication networks has always been rapidly progressive partly due to the demands of today’s data hungry users. This dissertation presents two key contributions to the body of knowledge in the evolving area of physical layer 4G+/5G communication technologies, especially in the domain of Higher-order MIMO detection and half-duplex relay network design. The initial part of this research investigates the development of a higher-order MIMO detection strategy for existing and future 4G+/5G receivers, from both a theoretical and practical perspective. A novel pre-processing Block QR decomposition technique has been proposed for an LTE receiver in a single-user interference-limited scenario as well as a point-to-point scenario with the results highlighting the complexity advantages and limitations in performance. The second part of this study involves a practical feasibility study of a novel two-phase three-part-message strategy for a physical layer half-duplex relay network, which features superposition coding and interference-aware successive interference cancellation decoding. A key aim of this study was to analyze the performance of the proposed link adaptation scheme in the non-asymptotic regime (finite block-length and discrete constellation signaling), and evaluate the spectral efficiency (SE) against the theoretical assumptions of asymptotically large block-lengths. An additional SE comparison with a non-cooperative two-hop relay transmission and point-to-point transmission strategy is also presented. The resulting outcomes reveal the SE gains that can be had by exploiting physical layer cooperation between the relay and base station.

The use of mobile communication has remarkably increased during the last years. It is the usage of 2G, 3G and in particular LTE that has increased. With every year that passes the con- sumers are putting higher demands on data rate and coverage. To solve the problem with coverage the signal can be relayed and thus amplified at the receiver end. To know if it’s pos- sible to relay the signal it’s important to know what signal is received locally. The company Network Expertise has given us a problem, due to that we want to investigate two things in this thesis. 1) Which signal parameters are relevant and which signal levels are good and bad for LTE. 2) How can signal measurements be done for 2G, 3G and 4G with an Android based system. To solve the first problem, a literature study was conducted where we found information about how past measurements have been made and what is relevant when measuring an LTE signal. The second problem was solved by developing an application for Android which implements the relevant measurements that was defined in the literature study. The application and the possibilities in Android have been reviewed and compared with similar tools for signal measurements. The relevant parameters for LTE measurements are RSRP, RSRQ, EARFCN and neighboring cells RSRP, RSRQ and EARFCN. Additional relevant parameters are ECI, MCC and MNC. LTE parameters which are possible to retrieve with an Android based telephone through An- droid API are RSRP, RSRQ and ECI (with some telephone models). The telephone must also support API level 17. For 3G it’s possible to retrieve RSCP, EcNo (with some telephone mod- els) and for 2G it’s possible to retrieve RSSI. MCC and MNC are both possible to retrieve in Android. Information about neighboring cells are not available for neither of the technologies. The quality level for the LTE parameter RSRP is great above -80 dBm level, good down to -90 dBm, moderate down to -100 dBm and bad below -100 dBm. Signal level for the LTE parame- ter RSRQ is great above -10 dBm, good down to -15 dBm, moderate down to -20 dBm and bad below -20 dBm. With the available version of Android is not sufficient to do advance signal measurements. / Användningen av mobil kommunikation har ökat kraftigt under de senaste åren. Det är användningen av 2G, 3G och speciellt LTE som har ökat. För varje år som går ställer konsumenterna högre krav på hastigheter och mobiltäckning. För att lösa problemen med täckning kan signalen förstärkas på mottagarsidan i en så kallad repeater. För att veta om det är möjligt att förstärka signalen är det viktigt att veta vilken signal som tas emot lokalt. Företaget Network Expertise har ett behov som leder oss fram till att undersöka två saker i denna rapport. 1) Vilka signalparametrar är relevanta och vilka signalnivåer är bra och dåliga för LTE? 2) Hur kan signalmätningar göras för 2G, 3G och 4G med ett androidbaserat system? För att lösa första problemet genomfördes en litteraturstudie där vi tog fram information om hur tidigare mätningar har gjorts och vad som är relevant vid mätning av en LTEsignal. Det andra problemet löstes genom att utveckla en applikation för Android som kan göra relevanta mätningar som definierades i förstudien. Applikationen och möjligheterna som erbjuds i Android har utvärderats och jämförts med liknande verktyg för att mäta signaler. De relevanta parametrarna för LTE-mätningar är RSRP, RSRQ, EARFCN och närliggande cellers RSRP, RSRQ och EARFCN. Ytterligare information som har relevans är ECI, MCC och MNC. LTE-parametrarna som går att hämta med en androidbaserad telefon via Android API är RSRP, RSRQ och ECI (med vissa telefonmodeller). Telefonen måste också stödja API-nivå17. För 3G går det att hämta RSCP och EcNo (med vissa telefonmodeller) och för 2G går det att hämta RSSI. MCC och MNC går båda att hämta via API. Information om närliggande celler är inte tillgängligt för varken 2G, 3G eller 4G. Kvalitetsnivån för LTE-parametern RSRP är utmärkt över -80 dBm insignal, bra ner till -90 dBm, medel ner till -100 dBm och dålig under -100 dBm. Kvalitetsnivån för LTE-parametern RSRQ är utmärkt över -10 dB, bra ner till -15 dB, medel ner till -20 dB och dålig under -20 dB. I dagsläget är androidplattformen inte riktigt mogen för att göra avancerade signalmätningar.