The purpose of this thesis is to explore the concept of resource scheduling and pricing and its relation to carrier aggregation. The first main topic is a modified Frank Kelly algorithm that allows for the use of utility functions that are piecewise concave, but not a member of a strictly \'diminishing return\' model. This adjustment to the Frank Kelly algorithm allows resource allocation to take into account devices with multiple applications. The second topic introduces the idea of scheduling resources in a carrier aggregation scenario assuming the carriers are scheduled sequentially. / Master of Science

Long Term Evolution (LTE) is becoming the first choice of operators when constructingthe new network infrastructure, because of its high throughput and lowlatency. Although the LTE can offer high speed data service as a benefit of widebandapplication, the large bandwidth also results in huge control signaling cost.This thesis studies how the available radio resources should be allocated todifferent users for the particular purpose. Three proposals are presented in thisthesis. The first two aim at maximizing the overall net capacity. The factors ofchannel conditions and control signaling cost are considered in the first proposalwhereas power control is supplemented as an additional factor in the second one.The third proposal aims at achieving a tradeoff between subframe efficiency andaverage data rate. Channel conditions and control signaling cost are taken intoconsideration.Resource blocks scheduling under a control signaling cost constraint is feasiblewith the knowledge of the channel condition of users. This is obtained from channelstate information directly. The first proposal studies how this scheduling isdone. The second proposal takes power allocation scheme into account. In termsof computational complexity, the methods of internal water-filling and externalwater-filling are described in the second proposal. The simulation results illustratethat the net capacity in the first proposal can be enhanced by about 5% -60% in the second proposal. The exact percentage of increase depends on differentcontrol signaling penalty.The third proposal discusses how to implement flexible subframe length underthe Rayleigh fading channel condition in the LTE system. The objective is toachieve subframe efficiency as high as possible, while maintaining the maximumaverage data rate. The simulation results illustrate that the optimal subframelength depends on control signaling cost penalty as well as on Doppler frequency.Finally, the fairness of the first proposal is compared with the improved versionsof Round Robin, Dynamic Allocation and Proportional Fair scheduling algorithms.The simulation results show that Round Robin and Dynamic Allocationoutperform the first proposal under a certain condition. / LOLA (Achieving Low Latency in Wireless Communication) is funded by EU FP7 (European Community’s Seventh Framework Programme).

[pt] O acesso sem fio de banda larga está se tornando uma realidade, não apenas para uso corporativo e doméstico, mas para usuários com mobilidade. Dos estimados 1.8 bilhão de pessoas que já utilizam banda larga desde 2012, cerca de dois terços serão consumidores de banda larga móvel e a maioria será servida por redes HSPA (High Speed Packet Access) e LTE-A (Long Term Evolution-Advanced), uma evolução para as redes 4G,capaz de oferecer velocidades acima de 500 Mbps. O planejamento celular tem como objetivo estabelecer a rede de rádio adequada e eficiente em termos de cobertura, capacidade, qualidade de serviço (QoS), custo, utilização de frequências, a implantação de equipamentos e desempenho. O objetivo deste trabalho é estudar dos métodos de planejamento de cobertura e capacidade de sistemas celulares LTE-Advanced e propor uma metodologia passo-a-passo para o planejamento inicial e dimensionamento do número de estações rádio base necessárias para atender uma determinada área de serviço com a capacidade requerida. Um estudo de caso é apresentado, ilustrando a aplicação da metodologia proposta. É apresentada também uma análise comparativa dos recursos requeridos para atender às especificações do projeto quando são utilizadas as bandas de frequência de 2.6 GHz, atualmente autorizada no Brasil, e a banda de 700 MHz, que está em consideração para uso futuro. Os resultados quantificam claramente as vantagens do uso da banda de 700 MHz em relação à banda de 2.6 GHz. / [en] The wireless broadband is becoming a reality, not only for corporate and domestic use, but for mobile users. Of the estimated 1.8 billion people already using broadband since 2012, about two thirds will be mobile broadband consumers and the majority will be served by HSPA (High Speed Packet Access) and LTE-A (Long Term Evolution-Advanced), an evolution to 4G networks, able to offer speeds up to 500 Mbps. The cell planning establishes a radio network properly and efficiently in terms of coverage, capacity, quality of service (QoS), cost, frequency usage, deployment of equipment and performance. The objective of this work is to study the methods of planning coverage and capacity of LTE-A cellular systems and propose a methodology step-by-step for the initial planning and dimensioning of the number of base stations required to meet a given service area with the required capacity. A study case is presented, illustrating the application of the proposed methodology. It also presented a comparative analysis of the required resources to meet the project specifications when used frequency bands of 2.6 GHz, nowadays licensed in Brazil, and the 700 MHz band, which is under consideration for future use. The results clearly quantify the advantages of the use of the 700 MHz band relative to the 2.6 GHz band.

<p>The use of relays is seen as a promising way to extend cell coverage and increase rates in LTE Advanced networks. Instead of increasing the number of base stations (BS), relays with lower cost could provide similar gains. A relay will have a wireless link to the closest BS as only connection to the core network and will cover areas close to the cell edge or other areas with limited rates.</p><p>Performing transmissions in several hops (BS-relay & relay-user) requires more radio resources than using direct transmission. This thesis studies how the available radio resources should be allocated between relays and users in order to maximize throughput and/or fairness. Time and frequency multiplexed backhaul is investigated under a full buffer traffic assumption. It is shown that the system will be backhaul limited and that the two ways of multiplexing will perform equally when maximising throughput and/or fairness. The analysis results in a set of throughput/fairness suboptimal solutions, dependant on how many relays are used per cell. The results are verified by simulations, which also show the limiting effects on throughput caused by interference between relays.</p><p>It is also analysed how the resource allocation should be done given non-fullbuffer traffic. A resource allocation that minimises packet delay given a certain number of relays per cell is presented. The analysis is based on queuing theory.</p><p>Finally some different schedulers and their suitability for relay networks are discussed. Simulation results are shown, comparing the throughput and fairness of Round Robin, Weighted Round Robin, Proportional Fairness and Weighted Proportional Fairness schemes. It is shown that allocating the resource among the relays according to the number of users served by the relays improves the fairness.</p>

The use of relays is seen as a promising way to extend cell coverage and increase rates in LTE Advanced networks. Instead of increasing the number of base stations (BS), relays with lower cost could provide similar gains. A relay will have a wireless link to the closest BS as only connection to the core network and will cover areas close to the cell edge or other areas with limited rates. Performing transmissions in several hops (BS-relay &amp; relay-user) requires more radio resources than using direct transmission. This thesis studies how the available radio resources should be allocated between relays and users in order to maximize throughput and/or fairness. Time and frequency multiplexed backhaul is investigated under a full buffer traffic assumption. It is shown that the system will be backhaul limited and that the two ways of multiplexing will perform equally when maximising throughput and/or fairness. The analysis results in a set of throughput/fairness suboptimal solutions, dependant on how many relays are used per cell. The results are verified by simulations, which also show the limiting effects on throughput caused by interference between relays. It is also analysed how the resource allocation should be done given non-fullbuffer traffic. A resource allocation that minimises packet delay given a certain number of relays per cell is presented. The analysis is based on queuing theory. Finally some different schedulers and their suitability for relay networks are discussed. Simulation results are shown, comparing the throughput and fairness of Round Robin, Weighted Round Robin, Proportional Fairness and Weighted Proportional Fairness schemes. It is shown that allocating the resource among the relays according to the number of users served by the relays improves the fairness.

IEEE 802.11p, the known standard for Vehicular Adhoc NETworks (VANETs), suffers from scalability issues and unbounded delay. In addition, the desire to use networks already in existence has created motivation for using cellular networks for vehicular applications. LTE-Advanced is one of the most promising access technologies in the wireless field, providing high data rate, low latency, and a large coverage area. Thus, LTE/LTE-A can be potential access technologies for supporting vehicular applications. Vehicular safety applications are based on broadcasting messages to neighboring vehicles. The vehicle location precision is crucial for safety applications. Thus, the freshness of the information (i.e. vehicle location) at the neighboring vehicles is very important. As LTE is an infrastructure-based network, all transmissions should pass through it. When the load of the network is high compared to the available resources, large delays may occur. The focus of this thesis is to propose solutions to make LTE suitable for vehicular safety applications. The first solution is to adapt the vehicular safety application to be suitable in LTE network. For this purpose, we propose an adaptation of the safety message generation rate. This adaptation uses a queueing model to compute the freshness of the information of vehicles at the destination, based on their message generation rates. It then adjusts the generation periods to provide a similar accuracy for all vehicles. The second approach is to modify the LTE and make it suitable for these kinds of applications. Thus, we proposed a scheduler for LTE which is suitable for vehicular safety applications. It considers the speed and location of the vehicles to allocate the resources to them for the transmission of safety messages. We also studied the message dissemination in the downlink, and proposed an efficient way to deliver the safety messages to the neighboring vehicles. Finally, we propose a scheme that uses both LTE-D2D and LTE-cellular communication for the transmission of safety messages. The centralized location information is used for Device-to-Device (D2D) pair discovery and resource allocation. The proposed scheme provides resource efficiency by enabling the reuse of the resources by vehicles. We also study the effect of the awareness range and period of updating location information at the server on resource usage and accuracy of D2D pair detection.

The evolved version of LTE is LTE-Advanced which is being developed by 3GPP. LTE-Advanced will meet or go beyond the requirements of the International Telecommunication Union (ITU) for the fourth generation (4G) radio communication standard known as IMT-Advanced. LTEAdvanced is primarily considered as a part of Release 10 of 3GPP specifications. The LTE-Advanced specifications will continue to be developed in subsequent 3GPP releases. The complete physical layer structure has been employed by using the latest 3GPP standards. Furthermore, technologies such as Orthogonal Frequency Division Multiplexing (OFDM) and Multiple Input Multiple Output (MIMO) have also been implemented and integrated with LTEAdvanced. The Multiple Access Scheme in Advanced Mobile radio system has to meet the specific requirements such as: high throughput, robustness, efficient Bit Error Rate (BER), high spectral efficiency, minimum delays, low computational complexity, low Peak to Average Power Ratio (PAPR), low error probability etc. In order to investigate the LTE-Advanced transceiver a thorough study has been carried out using MATLAB Simulink using AWGN and Rayleigh fading channel. This report investigates the performance of OFDMA and various MIMO configurations of LTEAdvanced physical layer, along with diverse modulation techniques such 16QAM and QPSK,the results are then demonstrated on BER and signal to noise ratio graphs. AWGN and Rayleigh fading models are also used to determine the performance of LTE-Advanced in presence of noise and fading.

Yes / Much attention has been paid to making 5G developments more en-ergy efficient, especially in view of the need for using high data rates with more complex modulation schemes within a limited bandwidth. The concept of the Doherty power amplifier for improving amplifier efficiency is explained in addi-tion to a case study of a 70W asymmetrical Doherty power Amplifier using two GaN HEMTs transistors with peak power ratings of 45W and 25W. The rationale for this choice of power ratio is discussed. The designed circuit works in the 3.4GHz frequency band with 200 MHz bandwidth. Rogers RO4350B substrate with dielectric constant εr=4.66 and thickness 0.035 mm is used. The perfor-mance analysis of the Doherty power amplifier is simulated using AWR MWO software. The simulated results showed that 54-64% drain efficiency has been achieved at 8 dB back-off within the specified bandwidth with an average gain of 10.7 dB.

[EN] Mobile communication systems are currently being developed with the aim of providing peak data rates up to 20 times higher to those of LTE-Advanced Rel 10. However, this performance improvement is often far from being the experimented performance by those users who are far from the Base Station (BS). In this sense, there exists a consensus on the fact that the best way to achieve the same quality for all users is with the use of heterogeneous networks composed of macrocells, microcells, femtocells, and relays. This dissertation addresses the use of Mobile Relays (MRs) to provide service to users who are at the cell-edge. MR is a natural extension of the fi xed relay in which users who are in the idle state could retransmit signals received from other transmitters to enhance data rates. This dissertation focuses on proposing and evaluating new techniques that manage the use of the MR in the new generation cellular networks. In particular, the dissertation studies MR from two complementary points of view. The first point of view investigates the MR management at the network level through a signaling protocol known as Media Independent Handover. The central idea of this mechanism is to use this signaling to connect the BS and the user in one of the following two manners. In the former, both entities are connected directly through the xG (x= 2, 3, 4, 5) wireless network. In the latter, there exists an xG connection between the BS and the MR and another one between the MR and the user through an IEEE 802.11 local wireless network. The investigations in this Thesis aim at fi nding a trade-of f between using multiple MRs and reducing signaling overhead. The second point of view deals with MR integration at air interface level. It consists in detecting, proposing, and evaluating new transmission techniques that solve the drawbacks derived from coherent detection. As with point-to-point systems, employing multiple antennas in a cooperative system can signi cantly improve the spectral efficiency of the systems with only one transmit antenna assuming that the channel estate information is available at the receiver. However, performing a coherent detection in a network assisted by relays consumes much more resources than a point-to-point network since the coherent detection requires the channel estimation of source-relay, relay-destination, and source-destination links. In this Thesis, the proposed solution is to use transmission techniques that do not need the channel knowledge to perform the detection. This dissertation evaluates the use of Single-User (SU) open-loop communication methods over temporally-correlated Rayleigh fading MIMO channels. On the other hand, in multi-carrier systems, the Thesis proposes to transmit the Grassmannian signaling (GS) in the virtual block formed by the coherence time and the coherence bandwidth. This proposal is due to the fact that GS achieves data rates approaching capacity over block-fading channels. However, this channel type is not common in real systems since channel correlation is often found in frequency, time, and space. For this reason, the next objective is to evaluate the performance of GS compared to the diversity transmission modes of LTE, analyzing the impact of user mobility and antenna correlation. Thanks to these investigations, we point that non-coherent systems are promising techniques in mobility scenarios with a high number of transmit antennas. This result motivates its relevance in the design of new SU open-loop transmission methods with multiple antennas. In downlink multi-user non-coherent scenarios, superposition coding and a suboptimum detection scheme are proposed. This detection system reduces the complexity respect to the maximum likelihood detection. Finally, this dissertation proposes that GS is transmitted in a new carrier type, where any reference signal is transmitted. In this way, the user would change its detection method to non-coherent. / [ES] Los sistemas de comunicaciones móviles están siendo desarrollados en la actualidad con el objetivo de ofrecer tasas de datos de pico hasta 20 veces mayores que las proporcionadas por LTE-Advanced Rel 10. Sin embargo, esta mejora en prestaciones está lejos de ser la experimentada por los usuarios que están lejos de la Estación Base (EB). En este sentido, existe un consenso en que la mejor manera de lograr la misma calidad para todos los usuarios es con el uso de redes heterogéneas formadas de macroceldas, microceldas, femtoceldas y relays. Esta Tesis estudia el uso del Relay Móvil (RM) para proporcionar servicio a usuarios que estén en el borde de la celda. El RM es una extensión natural del relay fijo en el cual los usuarios que están en reposo podrían retransmitir señales recibidas de otros transmisores para mejorar las tasas de datos. Esta Tesis se enfoca en proponer y evaluar nuevas técnicas que gestionen el uso del RM en las redes celulares de nueva generación. En particular, la Tesis estudia el MR desde dos puntos de vista complementarios. El primer punto de vista investiga la gestión del RM a nivel de red a través de un protocolo de señalización conocido como Media Independent Handover. La idea principal de este mecanismo es usar esta señalización para conectar la EB y el usuario en una de las siguientes dos maneras. En la primera, ambas entidades están conectadas directamente a través de la red inalámbrica xG (x=2, 3, 4, 5). En la segunda, existe una conexión xG entre la EB y el RM, y otra entre el RM y el usuario a través de una red inalámbrica local IEEE 802.11. Las investigaciones en esta Tesis buscan un compromiso entre usar múltiples RMs y reducir la carga de señalización. El segundo punto de vista trata de la integración del RM a nivel radio. Esto consiste en detectar, proponer y evaluar nuevas técnicas de transmisión que solucionen los inconvenientes derivados de la detección coherente. Como en los sistemas punto a punto, emplear múltiples antenas en un sistema cooperativo puede mejorar la efficiencia espectral respecto a los sistemas con una única antena transmisora asumiendo que el estado del canal está disponible en el receptor. Sin embargo, realizar una detección coherente en una red asistida con relays consume más recursos que una red punto a punto ya que la detección coherente requiere la estimación de canal de los enlaces fuente-relay, relay-destino y fuente-destino. La solución propuesta es usar técnicas de transmisión que no necesiten el conocimiento del canal para realizar la detección. Esta Tesis evalúa el uso de métodos de comunicación en lazo abierto a un único usuario sobre canales MIMO con desvanecimientos Rayleigh temporalmente correlados. Por otra parte, en sistemas multiportadora, se propone transmitir la Señalización Grassmannian (SG) en el bloque virtual formado por el tiempo de coherencia y el ancho de banda de coherencia. Esta propuesta se debe al hecho de que la SG alcanza tasas de datos cercanas a la capacidad en canales block-fading. Sin embargo, este tipo de canal no es común en sistemas reales puesto que la correlación del canal se encuentra a menudo en frecuencia, tiempo y espacio. Por esta razón, el siguiente objetivo es evaluar las prestaciones de la SG comparadas con los modos de transmisión de diversidad de LTE, analizando el impacto de la movilidad del usuario y la correlación de las antenas. Gracias a estas investigaciones, apuntamos que los sistemas no coherentes son técnicas prometedoras en escenarios con movilidad y un alto número de antenas transmisoras. En escenarios no coherentes multiusuario del enlace descendente, se propone utilizar superposition coding y un esquema de detección subóptimo que reduce la complejidad respecto a la detección de máxima verosimilitud. Finalmente, se propone que la SG sea transmitida en una nueva portadora donde ninguna señal de referencia se transmita. De esta forma, el usuar / [CAT] Els sistemes de comunicacions mòbils estan sent desenrotllats en l'actualitat amb l'objectiu d'oferir taxes de dades de pic fins a 20 vegades majors que les proporcionades per LTE-Advanced Rel 10. No obstant això, esta millora en prestacions està lluny de ser l'experimentada pels usuaris que estan lluny de l'Estació Base (EB). En este sentit, hi ha un consens en què la millor manera d'aconseguir la mateixa qualitat per a tots els usuaris és amb l'ús de xarxes heterogènies formades de macrocel·les, microcel·les, femtoceldas i relays. Esta Tesi estudia l'ús del Relay Mòbil (RM) per a proporcionar servici a usuaris que estiguen en el bord de la cel·la. El RM és una extensió natural del relay fix en el qual els usuaris que estan en repòs podrien retransmetre senyals rebudes d'altres transmissors per a millorar les taxes de dades. Esta Tesi s'enfoca a proposar i avaluar noves tècniques que gestionen l'ús del RM en les xarxes cel·lulars de nova generació. En particular, la Tesi estudia el MR des de dos punts de vista complementaris. El primer punt de vista investiga la gestió del RM a nivell de xarxa a través d'un protocol de senyalització conegut com Media Independent Handover. La idea principal d'este mecanisme és usar esta senyalització per a connectar l'EB i l'usuari en una de les següents dos maneres. En la primera, ambdós entitats estan connectades directament a través de la xarxa sense fil xG (x=2, 3, 4, 5) . En la segona, hi ha una connexió xG entre l'EB i el RM, i una altra entre el RM i l'usuari a través d'una xarxa sense fil local IEEE 802.11. Les investigacions en esta Tesi busquen un compromís entre usar múltiples RMs i reduir la càrrega de senyalització. El segon punt de vista tracta de la integració del RM a nivell ràdio. Açò consistix a detectar, proposar i avaluar noves tècniques de transmissió que solucionen els inconvenients derivats de la detecció coherent. Com en els sistemes punt a punt, emprar múltiples antenes en un sistema cooperatiu pot millorar l'efficiencia espectral respecte als sistemes amb una única antena transmissora assumint que l'estat del canal està disponible en el receptor. No obstant això, realitzar una detecció coherent en una xarxa assistida amb relays consumix més recursos que una xarxa punt a punt ja que la detecció coherent requerix l'estimació de canal dels enllaços font-relay, relay-destí i font-destí. La solució proposada és usar tècniques de transmissió que no necessiten el coneixement del canal per a realitzar la detecció. Esta Tesi avalua l'ús de mètodes de comunicació en llaç obert a un únic usuari sobre canals MIMO amb esvaïments Rayleigh temporalment correlats. D'altra banda, en sistemes multiportadora, es proposa transmetre la Senyalització Grassmannian (SG) en el bloc virtual format pel temps de coherència i l'amplada de banda de coherència. Esta proposta es deu al fet de que la SG aconseguix taxes de dades pròximes a la capacitat en canals block-fading. No obstant això, este tipus de canal no és comú en sistemes reals ja que la correlació del canal es troba sovint en freqüència, temps i espai. Per esta raó, el següent objectiu és avaluar les prestacions de la SG comparades amb els modes de transmissió de diversitat de LTE, analitzant l'impacte de la mobilitat de l'usuari i la correlació de les antenes. Gràcies a estes investigacions, apuntem que els sistemes no coherents són tècniques prometedores en escenaris amb mobilitat i un alt nombre d'antenes transmissores. En escenaris no coherents multiusuari de l'enllaç descendent, es proposa utilitzar superposition coding i un esquema de detecció subòptim que reduïx la complexitat respecte a la detecció de màxima versemblança. Finalment, es proposa que la SG siga transmesa en una nova portadora on cap senyal de referència es transmeta. D'esta manera, l'usuari canviaria el seu mètode de detecció a no coherent. / Cabrejas Peñuelas, J. (2016). Distributed cooperative MIMO in beyond 2020 wireless networks [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/63245 / TESIS

The demand for higher data rates for indoor and cell-edge users led to evolution of small cells. LTE femtocells, one of the small cell categories, are low-power low-cost mobile base stations, which are deployed within the coverage area of the traditional macro base station. The cross-tier and co-tier interferences occur only when the macrocell and femtocell share the same frequency channels. Open access (OSG), closed access (CSG), and hybrid access are the three existing access-control methods that decide users' connectivity to the femtocell access point (FAP). We define a network performance function, network productivity, to measure the traffic that is carried successfully. In this dissertation, we evaluate call mobility in LTE integrated network and determine optimized network productivity with variable call arrival rate in given LTE deployment with femtocell access modes (OSG, CSG, HYBRID) for a given call blocking vector. The solution to the optimization is maximum network productivity and call arrival rates for all cells. In the second scenario, we evaluate call mobility in LTE integrated network with increasing femtocells and maximize network productivity with variable femtocells distribution per macrocell with constant call arrival rate in uniform LTE deployment with femtocell access modes (OSG, CSG, HYBRID) for a given call blocking vector. The solution to the optimization is maximum network productivity and call arrival rates for all cells for network deployment where peak productivity is identified. We analyze the effects of call mobility on network productivity by simulating low, high, and no mobility scenarios and study the impact based on offered load, handover traffic and blocking probabilities. Finally, we evaluate and optimize performance of fractional frequency reuse (FFR) mechanism and study the impact of proposed metric weighted user satisfaction with sectorized FFR configuration.