Energy harvesting in cellular networks is an emerging technique to enhance the sus- tainability of power-constrained wireless devices. In this thesis, I consider the co- channel deployment of a macrocell overlaid with several small cells. In our model, the small cell base stations (SBSs) harvest their energy from environment sources (e.g., solar, wind, thermal) whereas the macrocell base station (MBS) uses conven- tional power supply. Given a stochastic energy arrival process, a power control policy for the downlink transmission of both MBS and SBSs is derived such that they can obtain their own objectives on a long-term basis (e.g., maintain the target signal-to- interference-plus-noise ratio [SINR] on a given transmission channel). To this end, I propose to use two di erent forms of stochastic game for the cases when the number of SBSs is small and when it becomes very large i.e. a very dense network. Numerical results demonstrate the signi cance of the developed optimal power control policy in both cases over the conventional methods.

In this thesis, our objective is to improve the energy efficiency and load balance for wireless networks. We first study the relationships between the base station (BS) on/off operation and traffic distribution. A cooperative power saving method called clustering BS-off (CBSO) scheme is proposed. Instead of adopting a unified and consistent BS-off scheme in the whole network, the proposed centralized and distributed CBSO schemes can adaptively group BSs in several clusters based on the traffic fluctuations with space and time. Second, to further improve the network load balance and energy efficiency in distributed manner, we propose a power efficient self-organized virtual small networking (VSN) protocol. A heuristic firefly algorithm is applied to arrange the BSs' operation in small groups based on the traffic level. By jointly considering the load balance, the effectiveness of the proposed algorithm is demonstrated based on the average and min-max traffic levels of BSs' groups. Finally, the importance of detailed BS operation between active and sleep modes is considered. The operating procedure of femtocell base station, i.e., HeNB, is modeled as an MAP/PH/1/k queueing system. Such queueing analysis particularly focuses on the HeNB vacation process with user priorities. The HeNB's power on/off scheme is modeled as alternative service and vacation periods. The hybrid access is regarded as high and low priority users in the queuing system. We further propose the adaptive service rate and vacation length (ASV) method, so that the HeNB can work in a more energy-efficient way while satisfying QoS requirements such as blocking probability and users waiting time. Simulation results show the effectiveness of the proposed strategies and the overall network energy efficiency can be improved significantly. / October 2016

The present doctoral thesis has been realized in accordance with the research line of Economy and Regulation in Telecommunications under the doctoral programme in Telecommunications of Universitat Politècnica de València. It has been developed on the basis of various research projects, especially the "Cooperation and Opportunity for Wireless Heterogeneous Networks Project" (TIN2010-21378-C02-02), which acted as my funding agent and the "S2EuNet-Security Project" . Mobile communications have undergone notable growth from their beginning up to the present day regarding devices and bandwidth available. Service providers have now to take the challenge of such increase. New technologies are being implemented to address the challenge and all of them belong to the world of mobile communications. This thesis will focus on the solutions provided by heterogeneous nets (HetNets) and, more speci¿cally, we will look at the Small Cells technology. It is starting to be widely deployed lately and allows for a visible increase in network capacity and a resulting enhancement in availability and coverage on the user side. Abundant research has proved that the integration of these technologies within markets is technically feasible. A marketing model is however still necessary which is able to prove its economic viability. A business model was laid out where a provider sets out to deploy small cells technology and stands as an incumbent service provider. The Theory of Games was used for the analysis of such models as it allows an insight of the decisions in equilibrium when entering into a competition among themselves and try the decisions of users need to be predicted. In this way we will manage to know the effect of such decisions over the pro¿ts of all the agents in the model. A clear picture will be thus obtained of the advantages of the implementation of the new technology in the market as well as of its effects over the incumbent service providers. This thesis intends to be a contribution towards the implementation of new technologies in the market of mobile technologies through the analysis of the competence between new service providers of Small Cells and an incumbent service providers along with the behaviour of the users of mobile communications. The result show that: users get a better service, the SSP pro¿ts are guaranteed and the entrance of the SSP improves the user comfort and social welfare. / Esta tesis se ha creado en el marco de la línea de investigación de Economía y Regulación de las Telecomunicaciones del programa de doctorado de Telecomunicaciones de la Universitat Politècnica de València, y se ha desarrollado en diferentes proyectos de investigación, en especial, el proyecto de "Cooperación yOportunismo enRedesde Acceso Inalámbricas y Heterogéneas" (TIN2010-21378-C02-02) y el proyecto S2EuNet-Security (FP7PEOPLE-2009- IRSES, 247083). Desde sus inicios las comunicaciones móviles han experimentado un gran crecimiento, tanto de dispositivos móviles como de cantidad de ancho de banda demandado, lo que ha provocado que los proveedores se encuentren con el desafío de hacer frente a este crecimiento. Para ello, se están implementando diferentes técnicas y tecnologías que se integran con el modeloactualdecomunicacionesmóviles.Enestatesisnoscentraremosenla solución que aportan las redes heterogéneas, especialmente en la tecnología de Small cells que se desplegado rápidamente en los últimos años y permite incrementar la capacidad de la red, así como obtener mejor disponibilidad y cobertura para los usuarios, pero falta un modelo de negocio claro donde se muestre su viabilidad económica. En esta tesis se plantea un modelo de negocio para un proveedor de servicio que despliega small cells y que compite como el proveedor de servicios incumbente. Para el análisis de este modelo se ha utilizado la Teoría de Juegos la cual ha permitido conocer las decisiones en equilibrio que toman los proveedores de servicio cuando compiten entre sí, así como las decisiones en equilibrio de los usuarios; de esta manera se ha obtenido el efecto de estas decisiones sobre los bene¿cios de todos los agentes del modelo y se han identi¿cado las ventajas y los inconvenientes que tiene la implementación de una nueva tecnología en el mercado. Esta tesis pretende ser una contribución al estudio de implementación de nuevas tecnologías en el mercado de comunicaciones móviles, más concretamente planteando modelos económicos que estudien su viabilidad a través del análisis de la competencia entre un nuevo proveedor se servicio de Small cells y el proveedor de servicio existente, y el comportamiento de los usuarios de comunicaciones móviles. Los resultados obtenidos muestran que los usuarios obtienen una mejor utilidad , el SSP siempre tiene unos bene¿cios garantizados, el MSP se ve obligado a competir y sus bene¿cios se ven perjudicados, además que la entrada del SSP mejora el bienestar de los usuarios y el bienestar social. / Aquesta tesi s'ha creat en el marc de la línia de recerca d'Economia i Regulació de les Telecomunicacions del programa de doctorat de Telecomunicacions de la Universitat Politècnica de València, i s'ha desenvolupat en diferents projectes de recerca, especialment, el projecte de Çooperació i Oportunisme en Xarxes d'Accés Sense ¿ls i Heterogènies"(TIN2010-21378-C02-02) i el projecte S2EuNet-Security (FP7PEOPLE-2009- IRSES, 247083). Des dels seus inicis les comunicacions mòbils han experimentat un gran creixement, tant de dispositius mòbils com de quantitat d'amplada de banda demandada, la qual cosa ha provocat que els proveïdors es troben amb el desa¿amentdeferfrontaaquestcreixement.Peraaixò,s'estanimplementant diferents tècniques i tecnologies que s'integren amb el model actual de comunicacions mòbils. En aquesta tesi ens centrarem en la solució que aporten les xarxes heterogènies, especialment a la tecnologia de Small cells que s'ha desplegat ràpidament en els últims anys i permet incrementar la capacitat de la xarxa, així com obtenir millor disponibilitat i cobertura per als usuaris, però falta un model de negoci clar on es mostre la seua viabilitat econòmica. En aquesta tesi es planteja un model de negoci per a un proveïdor de servei que desplega Small cells i que competeix com el proveïdor de serveis incumbent. Per a l'anàlisi d'aquest model s'ha utilitzat la Teoria de Jocs la qual ha permès conéixer les decisions en equilibri que prenen els proveïdors de servei quan competeixen entre si, així com les decisions en equilibri dels usuaris; d'aquesta manera s'ha obtingut l'efecte d'aquestes decisions sobre els bene¿cis de tots els agents del model i s'han identi¿cat els avantatges i els inconvenients que té la implementació d'una nova tecnologia al mercat. Aquesta tesi pretén ser una contribució a l'estudi d'implementació de noves tecnologies al mercat de comunicacions mòbils, més concretament plantejant models econòmics que estudien la seua viabilitat a través de l'anàlisi de la competència entre un nou proveïdor se servei de Small cells i el proveïdor de servei existent, i el comportament dels usuaris de comunicacions mòbils. Els resultats obtinguts mostren que els usuaris obtenen una millor utilitat, el SSP sempre té uns bene¿cis garantits, el MSP es veu obligat a competir i els seus bene¿cis es veuen perjudicats, a més que l'entrada del SSP millora el benestar dels usuaris i el benestar social. / Romero Chavarro, JC. (2017). Contribución al modelado y al análisis mediante Teoría de Juegos de la competencia entre operadores móviles en escenarios con tecnología "small cell" [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/85681 / TESIS

Yes / A compact design of multi-sector patch antenna array for 60 GHz applications is presented and discussed in details. The proposed design combines five 1×8 linear patch antenna arrays, referred to as sectors, in a multi-sector configuration. The coaxial-fed radiation elements of the multi-sector array are designed on 0.2 mm Rogers RT5880 dielectrics. The array operates in the frequency range of 58-62 GHz and provides switchable directional/omnidirectional radiation beams with high gain and high directivity characteristics. The designed multi-sector array exhibits good performances and could be used in the fifth generation (5G) cellular networks. / European Union’s Horizon 2020 research and innovation programme under grant agreement H2020-MSCA-ITN-2016 SECRET-722424

An ever increasing demand for mobile broadband applications and services is leading to a massive network densification. The current cellular system architectures are both economically and ecologically limited to handle this. The concept of small-cell networks (SCNs) based on the idea of dense deployment of self-organizing; low-cost, low-power base station (BSs) is a promising alternative. Although SCNs have the potential to significantly increase the capacity and coverage of cellular networks while reducing their energy consumption, they pose many new challenges to the optimal system design. Due to small cell sizes, the mobile users cross over many cells during the course of their service resulting in frequent handovers. Also, due to proximity of BSs, users (especially those at cell edges) experience a higher degree of interference from neighboring BSs. If one has to derive advantages from SCNs, these alleviated effects have to be taken care either by compromising on some aspects of optimality (like dedicating extra resources) or by innovating smarter algorithms or by a combination of the two. The concept of umbrella cells is introduced to take care of frequent handovers. Here extra resources are dedicated to ensure that the calls are not dropped within an umbrella cell. To manage interference, one might have to ensure that the neighboring cells always operate in independent channels or design algorithms which work well in interference dominant scenarios or use the backhaul to incorporate BS cooperation techniques. Further, small cell BS are most often battery operated, which calls for efficient power utilization and energy conservation techniques. Also, when deployed in urban areas, some of the small cells can have larger concentration of users throughout the cell, for example, hot-spots, which call in for design of SCNs with dense users. Also, with portable BSs, one has the choice to install them on street infrastructure or within residential complexes. In such cases, cell design and resource allocation has to consider aspects like user density, distribution (indoor/outdoor), mobility, attenuation, etc. We present the thesis in two parts. In the first part we study the cell design aspects, while the second part deals with the resource allocation. While the focus is on SCNs, some of the results derived and the tools and techniques used are also applicable to conventional cellular systems.

The exponentially increasing demand for high-speed wireless communications will no longer be satisfied by the traditional radio frequency (RF) in the near future due to its limited spectrum and overutilization. To resolve this imminent issue, industrial and research communities have been looking into alternative technologies for communication. Among them, visible light communication (VLC) has attracted much attention because it utilizes the unlicensed, free and safe spectrum, whose bandwidth is thousand times larger than the entire RF spectrum. Moreover, VLC can be integrated into existing lighting systems to offer a dual-purpose, cost-effective and energy-efficient solution for next-generation small-cell networks (SCNs), giving birth to the concept of optical attocell networks. Most relevant works in the literature rely on system simulations to quantify the performance of attocell networks, which suffer from high computational complexity and provide limited insights about the network. Mathematical tools, on the other hand, are more tractable and scalable and are shown to closely approximate practical systems. The presented work utilizes stochastic geometry for downlink evaluation of optical attocell networks, where the co-channel interference (CCI) surpasses noise and becomes the limiting factor of the link throughput. By studying the moment generating function (MGF) of the aggregate interference, a theoretical framework for modeling the distribution of signal-to-interference-plus-noise ratio (SINR) is presented, which allows important performance metrics such as the coverage probability and link throughput to be derived. Depending on the source of interference, CCI can be classified into two categories: inter-cell interference (ICI) and intra-cell interference. In this work, both types of interference are characterized, based on which effective interference mitigation techniques such as the coordinated multipoint (CoMP), power-domain multiplexing and successive interference cancellation (SIC) are devised. The proposed mathematical framework is applicable to attocell networks with and without such interference mitigation techniques. Compared to RF networks, optical attocell networks are inherently more secure in the physical layer because visible light does not penetrate through opaque walls. This work analytically quantifies the physical-layer security of attocell networks from an information-theoretic point of view. Secrecy enhancement techniques such as AP cooperation and eavesdropper-free protected zones are also discussed. It is shown that compared to AP cooperation, implementing secrecy protected zones is more effective and it can contribute significantly to the network security.

Abstract The aim of this thesis is to devise novel cooperative paradigms that allow small base stations (SBSs) to perform joint optimizations in the field of interference and spectral resource management, in an automated, self-organizing way. Fostering cooperation requires a careful negotiation process and incurs additional operational costs that can ultimately limit the scalability of such an approach. Hence, we design cooperative models around the self-organizing functions of small cell networks, through which each SBS dynamically adapts its own cooperative strategy to the current network status. In the first part of the thesis, we study the co-tier interference in the downlink of an underlay small cell tier. Showing that mutual interference is a limiting factor, we propose a cooperative scheme based on the concept of interference alignment. Thereby, the SBSs autonomously devise their cooperative strategy, select partner small base stations and suppress the mutual interference via alignment. In the second part, we extend the above problem by considering additional constraints posed by non-cooperative macro cell users sharing the spectrum with the SBSs. Due to the dimension of such a problem, we show that interference alignment solutions do not often exist, hence, we propose a distributed solution based on the concept of interference draining for solving the interfering signals in the space-frequency domain. Finally, we focus on inter-tier cooperation and propose an adaptive hybrid access policy based on spectrum leasing, which jointly enhances the SBSs' transmission capacity and the macro cell users' QoS . In the studied scenarios, we highlight how SBSs' individual performance is network-dependent, due to the shared nature of the spectrum and the network infrastructure. For addressing such issues, we use novel concepts from coalitional games in partition form in which the strategic decisions are optimized by accounting for external effects, such as interference or dynamic spectrum allocation. Based on the properties of optimality of coalitional games in partition form, the proposed cooperative solutions show two key features. First, by leveraging on decentralized strategic decisions, complex interference management techniques, such as interference alignment or draining, can be implemented in practical, scalable way. Second, although notable cooperative solutions exists for certain problem dimensions, the proposed algorithms are shown to be effective for a wide range of network sizes, by achieving significant data rate enhancement and low overhead. / Tiivistelmä Työssä käsitellään merkittäviä häiriön ja radioresurssien hallintaongelmia ja ehdotetaan käytännöllisiä yhteistoiminnallisuusmalleja, jotka tuottavat merkittäviä suorituskykyparannuksia, ja samaan aikaan ottavat huomioon yhteistyön kustannukset ja strategisten päätösten vaikutuksen piensolujen keskinäiseen suorituskykyyn. Työn ensimmäisessa osassa tutkitaan makro- ja piensoluverkon välistä häiriötä laskevalla siirtosuunnalla. Koska keskinäishäiriö osoittautuu merkittäväksi rajoittavaksi tekijäksi, ehdotetaan yhteistyömenetelmää, joka perustuu ns. häiriön laskostamiseen. Tällaisessa menetelmässä pientukiasemat päättävät itsenäisesti yhteistyöstrategiansa ja valitsevat ne tukiasemat, joiden kanssa tehdään yhteistyötä ja vaimennetaan keskinäishäiriötä laskostamalla. Työn toisessa osassa edellämainittua ongelmaa laajennataan ottamalla huomioon rajoitteet, jotka aiheutuvat samoja taajuusresursseja jakavista, mutta piensolutukiasemien kanssa yhteistyötä tekemättömistä makrosoluista. Ongelman laajuudesta havaitaan, että yleensä häiriön laskostusratkaisua ei löydy tällaisessa ongelmassa. Niinpä ehdotetaan hajautettua häiriön kohdennukseen perustuvaa ratkaisua, jossa häiriösignaalit lomitellaan tila-taajuustasossa. Työn viimeisessä osassa keskitytään eri tyyppisten tukiasemasolujen kesken käytävään yhteistyöhön ja ehdotetaan mukautuvaa taajuusspektrin vuokraamiseen perustuvaa hybridi-käyttöoikeusmenetelmää, joka parantaa piensolujen kapasiteettia ja makrosolukäyttäjien palvelun laatua. Kaikissa tutkituissa menetelmissä korostetaan kuinka yksittäisen pientukiaseman suorituskyky on verkosta riippuvainen johtuen jaetusta taajuuskaistasta ja verkkoinfrastuktuurista. Näissä skenaarioissa käytetään uusia ositukseen perustuvia ns. liittoumapelikonsepteja. Tämän tyyppisissä peleissä strategiset päätökset on optimoitu ottamalla huomioon ulkoiset tekijät kuten häiriö ja dynaaminen taajuuden allokointi. Ositukseen perustuvien liitoumapelien optimaalisuus- ja stabiilisuusominaisuuksien pohjalta ehdotetaan hajautettuja algoritmeja tutkittuihin ongelmiin. Ehdotetut yhteistoiminnalliset ratkaisut osoittavat kaksi avaintekijää. Ensinnäkin käyttämällä hajautettuja strategisia päätöksiä kompleksiset häiriönhallintatekniikat, kuten häiriön lomittelu ja kohdennus, voidaan toteuttaa käytännöllisesti siten, että hyöty-kustannussuhde on tasapainossa. Toiseksi, vaikka merkittäviä yhteistyöratkaisuja on olemassa tietyn dimensioisiin ongelmiin, ehdotetut algoritmit ovat osoittautuneet tehokkaiksi hyvin erikokoisissa verkoissa. Samalla on saavutettu merkittäviä datanopeusparannuksia ja hyvä skaalautuvuus.

Récemment, il y a eu une hausse massive du trafic dans les réseaux mobiles à cause de nouveaux services et applications. Les architectures actuelles des réseaux cellulaires ne sont plus capables de gérer de façon satisfaisante ce trafic. Les Réseaux de Petites Cellules (RPC), basées sur un déploiement dense de stations de bases portables, autoorganisantes et efficaces en termes d’énergie apparait comme une solution prometteuse à ce problème. Les RPC augmentent la capacité du réseau, réduisent sa consommation énergétique et améliorent sa couverture. Par contre, elles posent des défis importants en termes de design optimal. Dans cette thèse, des aspects liés au design cellulaire et à l’allocation de ressources dans les RPC sont traités. La thèse se compose de deux parties. Dans la première partie, le design cellulaire est étudié : une population statique d’utilisateurs est considérée, et la taille optimale de cellule maximisant le débit spatial est donnée en fonction du modèle de récepteur, des conditions radio et des partitions indoor/outdoor. En considérant des utilisateurs mobiles, la taille de cellule optimale est étudiée afin de minimiser le temps de service, et minimiser le blocage et la déconnexion en cours de communication, en fonction de la vitesse des utilisateurs et du type de trafic. Le problème de placement des stations de base optimal est traité en fonction de différents critères de qualité (maximisation de débit total, équité proportionnelle, minimisation de délai, équité max-min) pour différentes distributions d’utilisateurs et partitions de cellules. Le problème de scaling de capacité dans un RPC limité par l’interférence avec pré-codage est étudié, et la quantité optimale d’antennes par utilisateurs en fonction de l’interférence inter-cellules est dérivée. Dans le cadre d’un réseau “green”, pour une charge du réseau donnée, on étudie les politiques optimales en boucle ouverte, afin de maximiser soit une fonction coût du système (contrôle centralisé) soit des fonctions de coût de chacune des stations de base (contrôle distribué). Dans la seconde partie, nous étudions l’allocation de ressources, nous introduisons les concepts de d’équité T-échelle et équité multi-échelle. Ces concepts permettent de distribuer les ressources équitablement pour les différentes classes de trafic. Ces concepts sont illustrés par des applications au partage de spectre et à l’allocation de ressources dans les femto-cellules indoor/outdoor. L’allocation de puissance pour satisfaire les demandes de trafic des utilisateurs avec un grand nombre d’interféreurs est une tâche difficile. Ce problème est abordé, et nous proposons un algorithme universel qui converge vers une configuration de puissance optimale qui satisfait les demandes des utilisateurs dans toutes les stations de base. Les performances de l’algorithme sont illustrées pour différentes configurations du système et différents niveaux de coopération entre les stations de base. / An ever increasing demand for mobile broadband applications and services is leading to a massive network densification. The current cellular system architectures are both economically and ecologically limited to handle this. The concept of small-cell networks (SCNs) based on the idea of dense deployment of self-organizing; low-cost, low-power base station (BSs) is a promising alternative. Although SCNs have the potential to significantly increase the capacity and coverage of cellular networks while reducing their energy consumption, they pose many new challenges to the optimal system design. Due to small cell sizes, the mobile users cross over many cells during the course of their service resulting in frequent handovers. Also, due to proximity of BSs, users (especially those at cell edges) experience a higher degree of interference from neighboring BSs. If one has to derive advantages from SCNs, these alleviated effects have to be taken care either by compromising on some aspects of optimality (like dedicating extra resources) or by innovating smarter algorithms or by a combination of the two. The concept of umbrella cells is introduced to take care of frequent handovers. Here extra resources are dedicated to ensure that the calls are not dropped within an umbrella cell. To manage interference, one might have to ensure that the neighboring cells always operate in independent channels or design algorithms which work well in interference dominant scenarios or use the backhaul to incorporate BS cooperation techniques. Further, small cell BS are most often battery operated, which calls for efficient power utilization and energy conservation techniques. Also, when deployed in urban areas, some of the small cells can have larger concentration of users throughout the cell, for example, hot-spots, which call in for design of SCNs with dense users. Also, with portable BSs, one has the choice to install them on street infrastructure or within residential complexes. In such cases, cell design and resource allocation has to consider aspects like user density, distribution (indoor/outdoor), mobility, attenuation, etc. We present the thesis in two parts. In the first part we study the cell design aspects, while the second part deals with the resource allocation. While the focus is on SCNs, some of the results derived and the tools and techniques used are also applicable to conventional cellular systems.

Grâce aux avancées technologiques dans le domaine des réseaux cellulaires et des équipements mobiles, le nombre d'applications multimédia à haut débit dans les réseaux mobiles ne cesse d'augmenter. On prévoit que le trafic de données dans les réseaux mobiles en 2017 sera 13 fois plus important que celui en 2012. Pour satisfaire aux besoins des équipements mobiles, de nouvelles approches pour la gestion des ressources radio et des puissances de transmission sont requises.Dans le cadre de cette thèse, on s'intéresse à proposer des solutions pour remédier aux problèmes des interférences intercellulaires dans les réseaux mobiles de dernière génération. Nous enquêtons d'une manière exhaustive les différentes techniques de coordination des interférences intercellulaires existantes. Ces techniques sont qualitativement comparées, puis classées selon le taux de coopération requis entre les différentes stations de base, mais aussi selon leurs principes de fonctionnement. Nous abordons également le problème multicellulaire d'allocation des ressources et des puissances de transmission d'une manière centralisée. Nous formulons ce problème d'optimisation centralisé, puis nous le décomposons en deux sous-problèmes indépendants : l'allocation de ressources et l'allocation des puissances de transmission. De plus, une approche distribuée basée sur la théorie des jeux est proposée pour l'allocation des puissances de transmission. Les techniques centralisées de minimisation des interférences intercellulaires offrent la solution optimale au prix d'une grande charge de signalisation. Par contre, les solutions décentralisées réduisent le trafic de signalisation sans garantir l'optimalité de la solution obtenue. Nous proposons ensuite une heuristique de contrôle de puissance qui modifie localement l'allocation des puissances de transmission de manière à éviter le gaspillage d'énergie et pour réduire les interférences ressenties par les utilisateurs des stations de base voisines. Nous proposons également une technique autonome qui gère la distribution des ressources radio entre les différentes zones de chaque cellule. Cette technique répond aux besoins des utilisateurs dans chaque zone en adaptant la distribution des ressources d'une manière dynamique. Nous abordons aussi le compromis entre les techniques de gestion d'interférences intercellulaires centralisées et décentralisées. Nous proposons une approche hybride où l'allocation des ressources radio et des puissances de transmission est faite d'une manière coopérative entre les différentes cellules. Dans un premier lieu, les cellules voisines collaborent afin d'ajuster les puissances de transmission allouées aux ressources radio. Ensuite, la distribution des ressources entre les différentes zones de chaque cellule est modifiée localement, selon les besoins des utilisateurs dans chaque zone. / The exponentially increasing demand for mobile broadband communications have led to the dense deployment of cellular networks with aggressive frequency reuse patterns. The future Fifth Generation (5G) networks are expected to overcome capacity and throughput challenges by adopting a multi-tier architecture where several low-power Base Stations (BSs) are deployed within the coverage area of the macro cell. However, Inter-Cell Interference (ICI) caused by the simultaneous usage of the same spectrum in different cells, creates severe problems. ICI reduces system throughput and network capacity, and has a negative impact on cell-edge User Equipment (UE) performance. Therefore, Inter-Cell Interference Coordination (ICIC) techniques are required to mitigate the impact of ICI on system performance. In this thesis, we address the resource and power allocation problem in multiuser Orthogonal Frequency Division Multiple Access (OFDMA) networks such as LTE/LTE-A networks and dense small cell networks. We start by overviewing the state-of-the-art schemes, and provide an exhaustive classification of the existing ICIC approaches. This qualitative classification is followed by a quantitative investigation of several interference mitigation techniques. Then, we formulate a centralized multi-cell joint resource and power allocation problem, and prove that this problem is separable into two independent convex optimization problems. The objective function of the formulated problem consists in maximizing system throughput while guaranteeing throughput fairness between UEs. ICI is taken into account, and resource and power allocation is managed accordingly in a centralized manner. Furthermore, we introduce a decentralized game-theoretical method to solve the power allocation problem without the need to exchange signaling messages between the different cells. We also propose a decentralized heuristic power control algorithm based on the received Channel Quality Indication (CQI) feedbacks. The intuition behind this algorithm is to avoid power wastage for UEs that are close to the serving cell, and reducing ICI for UEs in the neighboring cells. An autonomous ICIC scheme that aims at satisfying throughput demands in each cell zone is also introduced. The obtained results show that this technique improves UE throughput fairness, and it reduces the percentage of unsatisfied UEs without generating additional signaling messages. Lastly, we provide a hybrid ICIC scheme as a compromise between the centralized and the decentralized approaches. For a cluster of adjacent cells, resource and power allocation decisions are made in a collaborative manner. First, the transmission power is adjusted after receiving the necessary information from the neighboring cells. Second, resource allocation between cell zones is locally modified, according to throughput demands in each zone.