Dissertations / Theses on the topic '4G LTE'

I den här rapporten redovisas resultatet av de mätningar som gjorts av Telias 4G-nät i form av datahastighet och signalstyrka, inom området av Umeå universitets Campus. Rapporten innefattar även en grundläggande teoretiskt beskrivning av de system och tekniker som berör ett 4G-nät. Mätningen utgick från 304 punkter över Campus området, mätningen skedde via att använda applikationen ”Bredbandskollen” på en mobiltelefon av modellen Huaweii P7-L10. En andra mätning genomfördes under ”Brännbollsyran” på Campus, från 26-28 maj. Syftet med den mätningen var att undersöka hur nätet klara av en högre belastning, och jämföra de mätvärdena mot dom tidigare. De slutsatser som dragits av rapporten är följande: Telias 4G nät lever upp till det kriterium om täckning och hastighet de själva uppgett. Mottagningen är bra på campusområdet, men inomhus kan den vara oberäknelig. Nätet klarade av belastningen under brännbollsyran, och gick fortfarande att använda bra trots hög belastning inom nätet.
This report presents the results of the mesaurements I’ve made on Telias 4G-network in the form of data rate and signal strength, withing the vicinity of Umeå University campus. This report also includes basic theoretical information about the techonolgy behind a 4G-network. The mesaurements emanated from 304 different locations around the campus area, mesaurements were made through the application ”Bredbandskollen” on a mobilephone of the model Huaweii P7-L10. A second measurement was made during the fesitval called ”Brännbollsyran” on Campus between 26-28 of may. It’s purpose was to examine how the 4G-network handled a heavier strain, and compare it’s measurements to the first one. The conclusions that have been made are the following: Telias 4G network lives up to the criteria concering coverage and speed they have stated. The reception on the campus are is good, however inside it can be unreliable. The network managed the strain during Brännbollsyran, and you could still use it sufficently, despite a heave load in the network.

The interest of Machine Type Communication (MTC) is increasing and is expected to play an important role in the future network society. In the process of increasing the number of connected devices, the coverage plays an important role. This thesis work aims to study the possibility of supporting coverage limited MTC-devices within LTE by extending the LTE coverage. It shows that coverage increase by means of repetition is a good candidate, which allows for a significant increase without hardware upgrades at a low cost in terms of radio resources. For inter-site distances up to 2500 m, the proposed repetition scheme with an increase of 20 dB allows for almost complete coverage where today’s LTE have significant lack of coverage. It also shows that even though the increased coverage implies higher resource usage, the limitation is not in the number of users supported, but rather the coverage at longer inter-site distances.

In the LTE mobile system, all cells use the same set of frequencies. This means that a user could experience interference from other cells. A method that has been studied in order to reduce this interference and thereby increase data rate or system throughput is to coordinate scheduling between cells. Good results of this have been found in different studies. However, the interference is generally assumed to be known. Studies using estimated interference and simulating more than one cluster of cells have found almost no gain. This thesis will focus on how to use information from coordinated scheduling and other traffic estimates to do better interference estimation and link adaption. The suggested method is to coordinate larger clusters and use the coordination information, as well as estimates of which cells will be transmitting, to make estimates of interference from other cells. The additional information from interference estimation is used in the link adaptation. Limitations in bandwidth of the backhaul needed to send data between cells are considered, as well as the delay it may introduce. A limitation of the scope is that MIMO or HetNet scenarios have not been simulated. The suggested method for interference estimation and link adaptation have been implemented and simulated in a system simulator. The method gives a less biased estimate of SINR, but there are no gains in user bit rate. The lesser bias is since the method is better at predicting high SINR than the base estimate is. The lack of gains regarding user bit rate may result from the fact that in the studied scenarios, users where not able to make use of the higher estimated SINR since the base estimate is already high. The conclusion is that the method might be useful in scenarios where there are not full load, but the users either have bad channel quality or are able to make use of very high SINR. Such scenarios could be HetNet or MIMO scenarios, respectively.

Autor no autoriza el acceso a texto completo de su documento hasta el 2/12/2020.
Ingeniero Civil Eléctrico
Durante el último proceso de tarificación de cargos de interconexión de las empresas de telefonía móvil que comenzó a principio de 2013 y culminó en 2014, se consideró un diseñó de una red eficiente con tecnología 3G incluida HSPA. En la actualidad, las tecnologías de redes móviles avanzan continuamente, hacia 4G y estándares superiores. De hecho durante el año 2014 se licitó en Chile la banda 700 MHz para desarrollo de redes 4G. El objetivo de esta memoria es aportar con un diseño de red 4G bajo las mismas premisas de la empresa eficiente que se ocupa en la regulación de los cargos de interconexión de la telefonía móvil en Chile. Para ello, se ha utilizado como punto de partida el modelo de red 3G+HSPA desarrollado por la Subsecretaria de Telecomunicaciones de Chile en la reciente fijación tarifaria, de la que se incluyó información relativa a la proyección de demanda y sus resultados. El diseño de red determina la cantidad de elementos 4G que satisfacen la demanda y la cobertura exigida. El trabajo se ha realizado sobre la base de la siguiente metodología: a) Se revisaron aspectos relacionados con arquitectura, planificación y diseño de redes móviles aplicados al último proceso de fijación de tarifas de interconexión en Chile. b) Se analizó el estado del arte en relación a aspectos de arquitectura, planificación y diseño de redes 4G/LTE. c) Se identificaron los elementos críticos de diseño de redes 4G/LTE para efectos de implementar un dimensionamiento de una red 4G/LTE. d) Se confeccionó un diseño de red 4G/LTE para atender una demanda equivalente a la utilizada en el último proceso de fijación de tarifas. El resultado de este trabajo concluyó en la determinación de las posibles eficiencias tanto técnicas como económicas que se producen al comparar el nuevo diseño de red 4G/LTE con un diseño de red 3G+HSPA, sobre la base de sensibilizar diferentes parámetros claves, tales como la banda de frecuencia de operación, la proyección de demanda, la capacidad máxima de equipos, precios unitarios, entre otros.

Long Term Evolution (LTE) known in the market as 4G LTE, it is an evolution of the GSM/UMTS standard. The overall aim of LTE was to provide a new radio access technology focusing on packet-switched data only. LTE has provided a new peak download rates, low data transfer latencies, and improved the support for mobility. 3Th Generation Partnership Project (3GPP) specialized that LTE released 10 and beyond known as LTE-advanced it is the second evolution of LTE. It has some services such as Coordinated Multipoint Transmission and Reception (CoMP), evolved Multimedia Broadcast and Multicast Service (eMBMS) with Multicast-Broadcast Single-Frequency Network (MBSFN). The development still continuous on LTE-advanced, it is intended to meet the requirement of advanced application that will become common in the wireless marketplace in future. The goals of this project is to simulate one of LTE-A services on LTE standard such as CoMP or/and eMBMS with MBSFN using OPENT LTE, and measure some statistic such as spectral efficiency and also some other statistics, describe centralization vs. decentralization in LTE, and synchronization in the base station in LTE. OPNET LTE support eMBMS with MBSFN, and don’t support CoMP, the simulation has been done by using eMBMS with MBSFN. Finally the objectives of the project has achieved, the result show that when eMBMS with MBSFN is implemented the throughput increased in the downlink to about 5.52 Mbps and in the uplink to about 5.18 Mbps, and also the system spectral efficiency increased in eNB1 from about 10.25 (bits/s/Hz/cell) to about 13.75 (bits/s/Hz/cell) and in eNB2 from about 10.25 (bits/s/Hz/cell) to about 17.25 (bits/s/Hz/cell). The project also answers if it is possible to have centralization in LTE, describe synchronization in the base station in LTE, and if OPNET is useful for big research.

Les communications sans fils sont devenues un outil fondamental pour les sociétés modernes. Les réseaux cellulaires sont le moyen préféré pour l’accès à Internet. L’augmentation de la capacité du réseau est étroitement liée au problème des interférences. Les réseaux coopératifs ont été largement étudiés dans les années récentes. Cette thèse porte sur deux techniques de coopération dans la voie descendante :La première partie étudie les effets de quantification et délais sur les informations de retour nécessaires pour la mise en opération des différentes techniques d’émission coordonnée, connues sous le nom de CoMP (Coordinated Multipoint Transmission). Cette technique qui promet des augmentations importantes sur la capacité du réseau en conditions idéales, or ses vrais résultats sous le feedback limité doivent être encore décrits de manière analytique. En particulier, pour les modes d’émission connus comme JT (Joint Transmission) et CBF (Coordinated Beamforming), des expressions analytiques ont été déduites pour calculer la capacité du réseau et la probabilité de succès de transmission.Finalement une nouvelle technique de coopération de réseau pour les récepteurs avancés du type SIC (Successive Interference Cancellation) est présentée. La condition mathématique qui garantit des gains de capacité grâce à l’utilisation des récepteurs SIC est obtenue. Pour en profiter, une méthode de coopération est nécessaire pour assurer une adaptation de lien adéquate pour que l’interférence soit décodable et le débit somme soit supérieur à celui atteint avec des récepteurs traditionnels. Cette technique montre des gains importants de capacité pour des utilisateurs en bordure de cellule
Wireless communications have become a fundamental feature of any modern society. In particular, cellular networks are essential for societal welfare but the increasing demand for data traffic set enormous scientific challenges. Increasing the network capacity is closely related to the problem of interference mitigation. In this regard, network cooperation has been studied in recent years and several different techniques have been proposed. In the first part, different transmission techniques commonly referred to as Coordinated Multi-Point Transmission (CoMP), are studied under the effect of feedback quantization and delay, unequal pathloss and other-cell interference (OCI). An analytical framework is provided, which yields closed-form expressions to calculate the ergodic throughput and outage probabilities of Coordinated Beamforming (CBF) and Joint Transmission (JT). The results indicate the optimal configuration for a system using CoMP and provide guidelines and answers to key questions, such as how many transmitters to coordinate, how many antennas to use, how many users to serve, which SNR regime is more convenient, whether to apply CBF or prefer a more complex JT, etc. Second, a new coordination technique at the receiver side is proposed to obtain sum-rate gains by means of Successive Interference Cancellation (SIC). The conditions that guarantee network capacity gains by means of SIC at the receiver are provided. To take advantage of these conditions, network coordination is needed to adapt the rates to be properly decoded at the different users involved. This technique is named Cooperative SIC and is shown to provide significant throughput gains for cell-edge users

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.

4G LTE is a new cellular phone network standard to provide both the capacity and Quality of Service (QoS) needed to support multimedia applications. Recent research in LTE has explored modifications to the current QoS setup, creating MAC layer schedulers and modifying the current QoS architecture. However, what has not been fully explored are the effects of LTE retransmission choices and capabilities on QoS. This thesis examines the impact of using acknowledgments to recover lost data over the wireless interface on VoIP, FTP and MPEG video applications. Issues explored include interaction between application performance, network transport protocols, LTE acknowledgment mode, and wireless conditions. Simulations show that LTE retransmissions improve FTP throughput by 0.1 to 0.8 Mb/s. With delay sensitive applications, like VoIP and video, the benefits of retransmissions are dependent on the loss rate. When the wireless loss rate is less than 20%, VoIP has similar performance with and without LTE retransmissions. At higher loss rates the use of LTE retransmissions adds degrading the VoIP quality by 71%. With UDP video, the choice of retransmissions or not makes little change when the wireless loss rates are less than 10%. With higher wireless loss rates, the frame arrival delay increases by up to 539% with LTE retransmissions, but the frame rate of the video decreases by up to 34% without those retransmissions. LTE providers should configure their networks to use retransmission policies appro- priate for the type of application traffic. This thesis shows that VoIP, FTP and video require different configurations in the LTE network layers.

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

Les travaux de thèse s'intéressent à la problématique de contrôle et de communication dans le domaine de la conception des systèmes numériques embarqués pour les applications de télécommunication de quatrième génération. La complexité des applications couplée aux besoins de productivité croissants impose de repenser les méthodologies de conception et les architectures sous jacentes. Afin de lever ces verrous, nous proposons plusieurs contributions originales. En effet, une méthodologie d'exploration d'un espace de conception ainsi qu'une architecture basée sur des noeuds de traitements homogènes et flexibles interconnectés à travers un réseau sur silicium sont proposées. Chaque noeud de traitement possède plusieurs blocs visant à exécuter efficacement et dynamiquement les applications de télécommunication. Pour répondre aux contraintes de faible consommation, nous proposons plusieurs solutions innovantes afin de minimiser cette métrique notamment au travers de techniques de migration de tâches
This PhD research aims to solve challenges about control and communication in the design of digital embedded systems for 4G telecom applications. The application complexity added to the increasing productivity gap force to think about new design methodologies and the underlying architectures. Several new research directions is proposed in this work. A methodology for design space exploration and a digital architecture based on homogeneous and flexible processing units interconnected by a Network-on-Chip is proposed. A processing unit is a cluster of DSPs controled by a MIPS processor to compute telecom applications. To meet low power constraints, we propose optimization techniques based on resource management including task migration

Internet access in rural areas of Latin America is deficient, since the rural population either does not have access to this technology or does it from public places at a very low speed connection. This situation does not happen with the TV which is more popular and accessible than the Internet, mobile telephony, and even radio. This is why is intended to use the characteristics of the TV broadcast services, specifically Digital Terrestrial Television (DTT) to provide Internet connectivity in places where only the TV signal arrives. Thus DTT technologies such as DVB-RCT published in April 2001 by the European Telecommunications Standards Institute (ETSI), which provides a dedicated wireless return channel in the VHF / UHF for concurrent access from many interactive user terminals using TDMA / OFDMA techniques. As well as DVB-T2 which was published in 2008 by the European standardization Forum (DVB) to efficiently transmit advanced television services such as high definition TV (HDTV) or dimensional TV (3D TV) [1] using OFDM will allow to design a new standard for better performance than RCT that takes advantage of the capacities that give robustness to DVB-T2 and which will be called DVB-RCT2 (Digital Video Broadcasting - Return Channel Terrestrial 2nd Generation), which would consist on a broadcast channel (DL) to receive information from the service provider to the end user, using any DTT technology such as ISDB-Tb, DVB-T or DVB-T2 for this purpose; while for reverse communication (UL) it would properly use the DVB-RCT2 architecture proposed in this PhD study. The aforementioned would make it possible for this new standard to be used throughout Latin America. To validate the design standard, it will be evaluated in terms of coverage and capacity with respect to its predecessor DVB-RCT, and then the channel conditions RCT2 will be emulated in a laboratory. Subsequently socio-economic studies of the new standard will be carried out in order to be able to provide internet connectivity services in rural areas. Finally, the possibility of using 4G wireless networks in the 700 MHz UHF band will be analyzed as well as the band of 1700 MHz (AWS).
El acceso a Internet en zonas rurales de América Latina es deficiente, puesto que la población rural o no tiene acceso a esta tecnología o lo hace desde lugares públicos a una muy baja velocidad de conexión. Esta situación no sucede con la TV la cual es más popular y accesible que el Internet, la telefonía móvil, e incluso que la radio. Es por esto que se pretende utilizar las características de los servicios de difusión de TV, específicamente los de Televisión Digital Terrestre (TDT) a fin de proporcionar conectividad a Internet en lugares donde solo llega la señal de TV. Es así que tecnologías de TDT como DVB-RCT publicada en Abril de 2001 por el Instituto de Normas de Telecomunicaciones Europeo (ETSI - European Telecommunications Standards Institute), que provee un canal de retorno inalámbrico dedicado en las bandas de VHF/UHF para el acceso concurrente desde muchos terminales interactivos de usuario usando técnicas TDMA/OFDMA. Así como DVB-T2 que fue publicado en 2008 por el foro de estandarización europeo (DVB) para transmitir eficientemente servicios avanzados de televisión como TV en alta definición (HDTV) o TV tridimensional (3D TV) [1] utilizando modulación OFDM; permitirán diseñar un nuevo estándar de mejores prestaciones que RCT que aproveche las capacidades que dan robustez a DVB-T2 y al cual se lo llamará DVB-RCT2 (Digital Video Broadcasting - Return Channel Terrestrial 2nd Generation), el mismo que constaría de un canal de difusión (canal descendente) para recibir información desde el proveedor del servicio hasta el usuario final, utilizando para esto cualquier tecnología de TDT como ISDB-Tb, DVB-T o DVB-T2; mientras que para la comunicación inversa (canal ascendente) utilizaría propiamente la arquitectura DVB-RCT2 propuesta en este estudio de doctorado. Lo anteriormente mencionado haría factible que este nuevo estándar pueda ser utilizado en toda Latinoamérica. Para validar el diseño del estándar, se lo evaluará en términos de cobertura y capacidad con respecto a su predecesor DVB-RCT, y después se emulará en laboratorio las condiciones del canal RCT2. Posteriormente se realizarán estudios socio-económicos del nuevo estándar a fin de poder proporcionar servicios de conectividad a Internet en zonas rurales. Por último, se analizará la posibilidad de utilizar redes inalámbricas 4G en la banda UHF de 700 MHz, así como en la banda de 1700 MHz (AWS).
L'accés a Internet en zones rurals d'Amèrica Llatina és deficient, ja que la població rural o no té accés a esta tecnologia o ho fa des de llocs públics a una molt baixa velocitat de connexió. Esta situació no succeïx amb la TV la qual és més popular i accessible que l'Internet, la telefonia mòbil, i inclús que la ràdio. És per açò que es pretén utilitzar les característiques dels servicis de difusió de TV, específicament els de Televisió Digital Terrestre (TDT) a fi de proporcionar connectivitat a Internet en llocs on només arriba el senyal de TV. És així que tecnologies de TDT com DVB-RCT publicada a l'Abril de 2001 per l'Institut de Normes de Telecomunicacions Europeu (ETSI - European Telecommunications Estàndards Institute), que proveïx un canal de retorn sense fil dedicat en les bandes de VHF/UHF per a l'accés concurrent des de molts terminals interactius d'usuari usant tècniques TDMA/OFDMA. Així com DVB-T2 que va ser publicat en 2008 pel fòrum d'estandardització europeu (DVB) per a transmetre eficientment servicis avançats de televisió com TV en alta definició (HDTV) o TV tridimensional (3D TV) [1] utilitzant modulació OFDM; permetran dissenyar un nou estàndard de millors prestacions que RCT que aprofite les capacitats que donen robustesa a DVB-T2 i al qual se'l nomenarà DVB-RCT2 (Digital Vídeo Broadcasting - Return Channel Terrestrial 2nd Generation), el mateix que constaria d'un canal de difusió (canal descendent) per a rebre informació des del proveïdor del servici fins a l'usuari final, utilitzant per a açò qualsevol tecnologia de TDT com ISDB-Tb, DVB-T o DVB-T2; mentres que per a la comunicació inversa (canal ascendent) utilitzaria pròpiament l'arquitectura DVB-RCT2 proposta en este estudi de doctorat. L'anteriorment mencionat faria factible que este nou estàndard puga ser utilitzat en tota Llatinoamèrica. Per a validar el disseny de l'estàndard, se l'avaluarà en termes de cobertura i capacitat respecte al seu predecessor DVB-RCT, i després s'emularà en laboratori les condicions del canal RCT2. Posteriorment es realitzaran estudis socioeconòmics del nou estàndard a fi de poder proporcionar servicis de connectivitat a Internet en zones rurals. Finalment, s'analitzarà la possibilitat d'utilitzar xarxes sense fil 4G en la banda UHF de 700 MHz, així com en la banda de 1700 MHz (AWS).
Radicelli García, CD. (2017). Diseño y validación de la segunda generación del estándar de TDT con canal de retorno inalámbrico, para proveer conectividad a Internet en zonas rurales en Latinoamérica [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/80288
TESIS

This work investigates the possibility to accelerate a procedure in 4G/LTE systems, known as control channel analysis. The aim is to perform the procedure in real-time on cheap and accessible hardware.An LTE decoder implemented in software is modified to perform the procedure.The modified software is analyzed and profiled. The most time-consuming decoding steps are identified and implemented in hardware description language.The results show an acceleration of the most time-consuming steps of almost 50 times faster compared to implementation in software only. Furthermore, the resource utilization of the hardware design scales linearly with respect to faster decode time, if necessary the acceleration can be increased. However, the results from the profiling and time measurements of the software show that the time requirement is violated by other decoding steps.The thesis concludes that an acceleration in hardware of the most time-consuming steps is possible. However, to satisfy the time requirement further decode steps are required to be accelerated and/or a faster processor can be used.

Since Mobile network operator (MNO) relies on many Business Support Systems (BSS) and Operation Support Systems (OSS) it should be assured that operator’s systems supports the requirements of the future.This thesis shall focus on the “start-to-end” aspects that must be considered to ensure that International Roaming continues to operate flawless. The thesis experience Long Term Evolution (LTE) in case of international roaming by measuring the end to end location update delay.In order to evaluate the LTE performance of international roaming, the delay time has been measured by the means of tracing tools for several different international roamers and the results has been compared with the results achieved for local user. The outcome has been compared with the respecting results in 3G network the statistical results has been provided and the graphs has been plotted to study the performance.Based on the results obtain on this thesis, it has been concluded that local user acts more stable to get attach to the network, i.e. there are less fluctuation in delay times for local user. Also the delay time in 3G networks is more than the LTE networks, however 3G networks acts more stable and there are less fluctuation to get connects to 3G networks.

El objetivo general de esta memoria de título, es estudiar la tecnología LTE (Long Term Evolution) y el impacto que podría tener, la incorporación de ésta, en Chile. Específicamente, se contempla el desarrollo de los Servicios de Valor Agregado (SVA), tomando como modelo de referencia la evolución del mercado internacional, en esta incipiente tecnología y, con este análisis, se pretende pronosticar el futuro del mercado móvil nacional. Este estudio se centra en dos puntos relevantes de una implementación de tecnología: por un lado, la tecnología misma y las capacidades que ésta puede entregar y, por otro, el mercado nacional en conjunto con los SVA existentes. En sus inicios, la telefonía móvil fue diseñada para la transmisión de voz, debido a las limitaciones que poseía la tecnología de esa época. Hoy en día, la tecnología móvil permite dar servicio de datos de banda ancha, por lo que es posible brindar una mayor gama de servicios y aplicaciones. Se ha comprobado que el crecimiento en el ARPU de los clientes, va directamente ligado con el despliegue de más y mejores servicios de valor agregado. En particular, estos servicios mejoran la experiencia de usuario, lo cual tiene una directa relación con el aumento de la fidelidad de los clientes. Además de esto, se debe considerar que el mercado chileno se caracteriza por gran demanda de servicios tecnológicos y la rápida absorción de éstos. Los sistemas móviles de tercera generación (3G), se han desarrollado como evolución de los sistemas existentes de segunda generación (2G) a saber, GSM y CDMA (IS-95). Los principales criterios del desarrollo de la 3G, recogidos por el proyecto de la Unión Internacional de Telecomunicaciones (UIT) en [IMT2000], fueron el proporcionar una interfaz radio de mayor capacidad de usuarios y que ofreciera mayores velocidades de usuario (en teoría 2 Mbps), objetivos que se lograron en la primera entrega de las especificaciones conocidas como Release 99, en UMTS y Release-A en CDMA2000. Desde el punto de vista de servicios, no se plantearon innovaciones importantes, lo cual incidió en la adopción inicial de la tecnología 3G, por parte de los usuarios. El trabajo ha continuado dentro del 3GPP y 3GPP2 (organismos encargados de la especificación técnica de los sistemas 3G UMTS y CDMA2000 respectivamente), para evolucionar los sistemas 3G, produciendo nuevas entregas que incluyen mejoras sustanciales en la gestión de recursos radio, proporcionando nuevos canales radio que soportan mayores velocidades: el HSPA; un nuevo dominio de comunicaciones multimedia sobre IP que abre la puerta a un nuevo escenario de servicios de tiempo real, sobre el dominio de conmutación de paquetes; asimismo, se ha completado la especificación de la integración de otras redes de acceso, tales como LCR-TDD (Low Chip Rate TDD, especificado por China) y WLAN (Wireless LAN). Posterior a esto, tanto el 3GPP como el 3GPP2, entregan la especificación pública de nuevos modelos de red (LTE – Long Term Evolution para UMTS y UMB – Ultra Mobile Wideband para cdma2000), con interfaces radio con más capacidad, más simples, mejor adaptados a las redes IP y con una mejor estructura de costes operacionales y de despliegue, que algunos ya denominan 4G. Se espera que con la entrada de LTE al mercado internacional, se logre finalmente el despegue del internet móvil, de servicios como la transmisión de datos a más de 300 metros y videos en HD. La novedad de LTE, es la interfaz radioeléctrica basada en OFDMA, para el enlace descendente (DL) y SC-FDMA, para el enlace ascendente (UL). La modulación elegida por el estándar 3GPP, hace que las diferentes tecnologías de antenas (MIMO), tengan una mayor facilidad de implementación, esto favorece, según el medio, de hasta cuadruplicar la eficacia de transmisión de datos. En el área de redes, el principal aspecto de la investigación en las redes 4G, es la integración de distintas tecnologías radio, sobre una red basada en IP, que proporcione movilidad de usuario y que soporte la calidad de servicio requerida por las aplicaciones. Las redes de acceso móvil en la 4G y los servicios de valor agregado que éstas puedan soportar, constituyen el marco general en que se encuadra esta memoria de título.

Mestrado em Engenharia Eletrónica e Telecomunicações
This work alludes to 4G LTE technology. Techniques used for the same technology are described namely precoding and Alamouti coding and decoding. An Alamouti’s 4G system implemented to FPGA using the Xilinx System is introduced. The work also addresses the PAPR problem due to the reference pilots in the platform being generated all in phase. In this work a random pilot generator was implemented which combats the high peak power. In the receiver it was taken into account the new generation method to perform channel estimation correctly. A technique is discussed to increase the energy efficiency of the system based on PAPR reduction.
O presente trabalho faz alusão à tecnologia 4G LTE. São descritas técnicas usadas na mesma tecnologia nomeadamente de precoding e codificação e descodificação Alamouti. É introduzido um sistema Alamouti 4G implementado para FPGAs usando o programa System Generator da Xilinx. O trabalho também aborda o problema do PAPR devido aos pilotos de referência na plataforma estarem sendo gerados todos em fase. Neste trabalho, um gerador aleatório de pilotos foi implementado que combate a potência de pico (PAPR). No receptor levou-se em conta o método desta nova geração para realizar a estimativa de canal corretamente.

This thesis presents a comprehensive analysis of the LTE-Advanced Physical Downlink Shared Channel (PDSCH) in outdoor environments. Bit accurate and a Received Bit mutual Information Rate (RBIR) simulators are developed and used for system and link level performance evaluation studies. The RBIR is shown to reduce simulation run time by a factor of more than 300. The radio channel is modelled using a site-specific 3D ray-tracing tool combined with measured BS and UE 3D antenna patterns. A 3D extension of the standardized 2D ITU-R channel model is implemented by exploiting ray tracing statistics. A comparison study between the 2D ITU-R, extended 3D ITUR, and 3D ray tracing channel models is performed to highlight the advantages of 3D modelling over 2D modelling and the deficiencies of the ITU-R models compared to 3D ray tracing. Performance results on the impact of handset rotation show higher throughputs for UEs at 45° rotation in elevation (single antenna system) as a result of higher K factors and total received power levels. For a 2x2 MIMO, the study recommends an antenna switching scheme for tablet UEs that activate two from three antennas based on device orientation to achieve the highest channel capacity. The study also suggests the planar array deployment of antennas in both smartphones and tablets for 4x4 MIMO systems in order to reduce handset rotation sensitivity and to achieve higher capacity. This thesis also considers carrier aggregation (CA) between the 800 MHz and 2.6 GHz bands. Results show similar average throughput vs SNR performance in both bands. Furthermore, for mobile users in specific routes with inter cell interference (lCI) the 800 MHz band is shown to have no significant improvement on downlink throughput. Hence there are no additional advantages of intra-band CA at 800 MHz compared to inter-band CA between the two bands. Finally the thesis provides a detailed analysis of the effect ofICI on LTE-Advanced for different macro cell diameters, base station (BS) antenna heights and carrier frequencies. A 3D ray-tracing tool is used to model the communication channel between the base stations (main and interfering links) and user equipment (UE) terminals. The Inter Site Interference (ISI) is first modelled in terms of its Dominant Interference PropOttion (DIP) and then validated using previously repOtted field measurements in London. ISI and Inter Sector Interference are modelled as a function ofUE relative position from the main BS. System performance is evaluated in terms of average spectrum efficiency, cell edge throughput and outage probability. Two 3D analogue beamforming algorithms are proposed to mitigate the harmful effects ofIC!. These are applied at the BS and/or the UE and the obtained results are compared with a more traditional fractional frequency reuse deployment. Simulations demonstrate that the proposed beamforming algorithms provide significant system level improvements, especially for low BS antenna heights. With 1 Oxl 0 and 2x2 antenna alTays at the BS and UE respectively, the MaxMin-BF algorithm provides an average spectrum efficiency of3.6 bps/Hz and a cell edge throughput of 0.56 bps/Hz up to a cell diameter of 1250 m. ImpOttantly, these results satisfy the IMT-Advanced requirements for candidate 4G and beyond Radio Interface Technologies (RITs). Furthermore, the proposed techniques outperform fractional frequency reuse method.

PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
Nesta dissertação é investigada, por meio de simulações computacionais, a utilização do conceito de rádio cognitivo considerando a técnica de sensoriamento espectral aplicada às femtocélulas do sistema móvel LTE Release 10 para reduzir os problemas de interferência entre camadas (cross-tier) existentes em um cenário de coexistências das redes heterogêneas (femtocélulas e macrocélulas). Além disso, é investigada a interferência gerada por parte das femtocélulas LTE Release 10 em receptores de TV Digital operando em bandas de frequência adjacentes. Neste caso, além da simulação computacional foram realizadas medições em cenários de coexistência da femtocélula LTE e do Sistema Brasileiro de TV Digital na banda de frequência de 700 MHz.
This dissertation investigates, using computer simulation, the use of spectrum sensing Cognitive Radio concept applied in femtocells of the LTE Release 10 mobile system in order to reduce the interference cross-tier problems that exists in the coexistence scenario of a heterogeneous network (femto-macrocells). Furthermore, the interference produced by LTE Release 10 femtocells in TV Digital receivers operating in adjacent frequency bands was investigated. In this case, besides the computer simulations measurements were performed in an experimental setup implementing coexistence scenarios of the LTE femtocell and the Brazilian Digital TV System at the 700 MHz frequency band.

The aim is to define the market data services, with an emphasis on newly developed LTE network. Furthermore, to analyze the current state of Telefónica Czech Republic a.s. and its surroundings. Define the main LTE development strategy in the approach to the development of the network in different variants and evaluate which of these strategies is the preferred one. The selected strategy is then confronted with the benefits that the development of LTE networks will bring and in the end the decision to develop the network in the future is evaluated.

The number of wireless connected devices are growing exponentially and the importance of this research area is growing as well to meet the known and looming challenges and expectations. The 5:th Generation telecommunications standard is partly embodied by the Machine-to-Machine (M2M) and Internet of Things (IoT) technologies and standards to handle a big part of these devices and connections. An example within the IoT paradigm is military training systems where each system can consist of thousands of battery operated mobile devices and their shifting requirements shall be fullled in an energy-aware manner to increase battery operating times. Military training radio networks enables realistic combat training. The services and features provided in commercial telecommunications networks are desirable in these often proprietary and task specic networks, increasing capabilities and functionalities. To facilitate the current and future R&D of LTE based networks for adoption in military training networks and services this doctoral thesis intends to provide the starting ground for the energy-aware LTE based wireless communications. The thesis first presents general solutions on how to meet traffic deadlines in wireless networks for large number of nodes, and then continues with solutions for energy-aware LTE-based communications for the User Equipments (UEs). The work builds on the problem formulation how to provide energy-aware resource handling for LTE-based military training networks from where three research questions are derived. From the research questions we derive different hypotheses and then test these within the investigated area to answer the research questions. The contributions of this work are within areas of resource handling and power saving for mobile devices. In the first area an admission control using deterministic analysis is proposed fullling traffic requirements for military training mobile nodes. This admission control is enhanced for multiple-channel base stations, and evaluated using mobile nodes with different heterogeneous traffic requirements. In the second part energy-awareness is in focus for LTE/LTE-A based networks. The main power saving method for LTE/LTE-A UEs, Discontinuous Reception (DRX) mechanism, is evaluated and models for DRX in Idle and Connected state are proposed including metrics for wake-up delay and power saving. Additionally a mean queuing delay analysis is proposed for a variant of the Connected state DRX. Using these models and metrics, practical design guidelines for tuning of DRX parameters are proposed, including optimization of DRX parameters for either minimizing delay or maximizing power saving.

Die vorliegende Diplomarbeit behandelt den Vergleich von QoS- und Mobilitätsmechanismen in der LTE/SAE-Architektur. Nach der Einführung in die LTE/SAE-Architektur wird dargestellt, wie die QoS und die Mobilität im Standard des 3GPP gewährleitet wird. Danach erfolgt eine Untersuchung der Technologien PMIP, Ethernet und MPLS, ob sie sich als Alternativen für die standardisierten Mechanismen eignen. In einem weiteren Kapitel wird ein eigenes Konzept zur QoS- und Mobilitätsverwaltung vorgestellt, und es erfolgen erste Betrachtungen. Abschließend wird ein Ausblick gegeben, wie das vorgestellte eigene Konzept weiter ausgebaut werden könnte.

La norme 3G/UMTS a permis de développer les premières applications multimédia pour téléphones et tablettes mobiles. Le nouveau standard 4G/LTE (Long Term Evolution) a pour objectif le très haut débit mobile. Dans ce standard, beaucoup d'efforts ont portés sur la reconfiguration automatique des réseaux en fonction de la demande des clients dans un processus appelé Self-Organizing Network (SON). Le travail de cette thèse s'inscrit dans cette direction. La reconfiguration de réseaux est comprise principalement dans le sens des modèles, des méthodes et des outils pour analyser les indicateurs remontés du réseau et configurer automatiquement les paramètres. Nous avons essentiellement travaillé sur les paramètres des aériens, l'allocation des fréquences, des puissances d'émission et des inclinaisons verticales.Dans cette optique, étant donné la forte variabilité des données d'entrée de l'optimisation issues des remontées de réseau, cette thèse porte sur les modèles et algorithmes d'optimisation robuste dans le contexte de l'optimisation sous contraintes. L'optimisation robuste fait référence à un ensemble de procédés pour proposer des solutions à des problèmes combinatoires dans un contexte de données incertaines et de scénarios variables dans le temps. Une première partie est dédiée à l'état de l'art et présente les principes des Self-Organizing Network (SON). La deuxième partie est consacrée à l'état de l'art des méthodes en optimisation robuste. En troisième partie nous présentons la modélisation mathématique du problème d'optimisation pour lequel les données de trafic (répartitions des clients sur la zone de service et leurs demandes respectives) prennent des valeurs variables dans le temps. Une phase de diagnostic sur le fonctionnement du réseau à partir des données, et une étude de sensibilité des solutions vis-à-vis des variations dans la réalisation des données ont été faites en quatrième partie avec des algorithmes de recherche locale. La cinquième partie présente le travail de conception, développement et test sur scénarios, d'une Recherche Tabou ainsi qu'une analyse approfondie sur les méthodes de pilotage envisagées pour les SON en 4G.

L'objectif de cette thèse est le déploiement et l'évaluation d'une plate-forme de télé-échographie mobile, utilisée pour fournir un diagnostic et des soins à distance dans des milieux médicalement isolés. La plateforme intègre de nouveaux concepts qui permettent de l’utilisation de la télé-échographie robotisée sur les réseaux sans fil 3G, 4G et 5G pour satisfaire au transfert de qualité des vidéos ultrasonores pour un diagnostic médical robuste. Ce travail contribue au domaine des Sciences et Technologies de l'Information et de la Communication appliquées au secteur de la santé et en particulier à la robotique médicale téléopérée. Les principales contributions de la thèse sont : I. Un état de l’art des systèmes télé-robotiques appliqués au médical menée sur la base de publications écrites entre 2004 et 2016, II. L'évaluation objective et subjective (clinique) de la qualité vidéo a démontré que les normes H.264/AVC et HEVC peuvent atteindre une qualité vidéo sans perte de diagnostic à des débits (1024 et 2048 Kbps) bien en deçà des débits de données supportés par les réseaux 4G. Les normes de codage vidéo antérieures (Mpeg-4, Mpeg-2) ne peuvent pas être utilisées pour le diagnostic clinique à ces débits car elles présentent une perte d'information pour le diagnostic médical, III. Les experts médicaux ont apprécié la réactivité dynamique mécanique de la plate-forme en raison du faible délai présenté par les canaux LTE. La limitation la plus importante soulevée par l'expert médical, empêchant une évaluation globale clinique favorable au diagnostic, était le positionnement initial du robot sur le corps du patient et son déplacement vers l'obtention d’une échographie cardiaque, Les résultats fournissent une forte indication que la plate-forme télé-échographie robotisée peut être utilisée pour fournir un diagnostic fiable et à distance sur les réseaux sans fil émergents 4G et au-delà
The objective of this Thesis was the deployment and evaluation of an end-to-end mobile tele-echography platform used to provide remote diagnosis and care within medically isolated settings. The platform integrates new concepts that enable robotized tele-echography over commercially available 4G and beyond mobile networks for rendering diagnostically robust medical ultrasound video. It contributes to the field of Information and Communication technologies applied in the healthcare sector. The main contributions of the Thesis are: I. A systematic review on the state of the art in medical telerobotic systems was conducted based on publications of the last decade, and more specifically between the years 2004 to 2016. II. Both objective and subjective (clinical) video quality assessment demonstrated that H.264/AVC and HEVC standards can achieve diagnostically-lossless video quality at bitrates (1024 and 2048 Kbps) well within the LTE supported data rates. Earlier video coding standards (Mpeg-4 & Mpeg-2) cannot be employed for clinical diagnosis at these rates as they present loss of clinical information.III. Medical experts highly appreciated the proposed platform’s mechanical dynamic responsiveness due to the low end-to-end delay (latency) facilitated by LTE-channels. The most important limitation raised by the medical expert and prevented higher overall rating and ultimately clinical QoE was the robot initial positioning on the patient’s body and navigation towards obtaining the cardiac ultrasound. IV. Results provides a strong indication that the proposed robotized tele-echography platform can be used to provide reliable, remote diagnosis over emerging 4G and beyond wireless networks

Mestrado em Engenharia Eletrónica e Telecomunicações
The main goal of this dissertation is the development and evaluation of new techniques to be used in new generation of wireless comunication devices. It focuses on the usage of multiple antennas (MIMO), precoding and the usage of spatial multiplexing in disregard of diversity techniques. This makes possible to increase data rates considerably. Throughout the document, are shown several multiplexing techniques, theoretical information about wireless propagation, and multiple antennas techniques. It was proposed and implemented a spatial multiplexing system. Firstly it was implemented in Matlab, with two precoders tested: Zero Forcing (ZF) and Minimum Mean Square Error (MMSE). Subsequently a System Generator implementation (this time with only ZF equalizer) was made in order to make possible the migration to FPGAs. Both implementations were tested and validated, we also concluded that ZF based pre-coder had a lower Bit Error Rate for the same Signal to Noise Ratio (SNR).
O tema central deste trabalho de dissertação centra-se no desenvolvimento e teste de novas técnicas para utilização em comunicações sem-fios de nova geração. Foca-se no uso de várias antenas, técnicas de pré-codificação e no uso de multiplexagem espacial em detrimento de diversidade, de forma a aumentar a largura de banda. Ao longo do documento são apresentadas várias técnicas de multiplexagem, bem como bases teóricas de propagação de sinais rádio e técnicas baseadas no uso de várias antenas no emissor e recetor (MIMO). Foi proposto um sistema de pré-codificação baseado em diversidade espacial. A implementação e teste do bloco pré-codificador SMMIMO foi realizada em primeiro lugar usando um simulador Matlab para efeito de comparação. Foram implementados dois equalizadores: Zero Forcing (ZF) e Minimum Mean Square Error (MMSE); posteriormente procedeu-se à implementação em System Generator de um pré-codificador com equalização ZF, de forma a ser possível a sua implementação em FPGAs. Esta implementação foi igualmente validada por comparação com o bloco implementado em Matlab.

This diploma thesis focuses on the telecommunications field and specifically on the analysis of the Czech telecommunications market. Theoretical part of the thesis is focused on the historical development of telecommunications in terms of technological trends in the world and their subsequent transfer to Czech market. The practical part deals with the analysis of the Czech market, according to selected criteria, particularly in terms of privided services, their quality and technological solutions. The emphasis is on the analysis of operation of the mobile telecommunication and data services providers in the Czech Republic. The result of this diploma thesis is the analysis of the current state of the Czech telecommunications market in common with positive forecasts.

Cette thèse porte sur la conception d’amplificateurs de puissance reconfigurables en technologie CMOS avancée pour une application cellulaire de 4ème génération. Dans les systèmes de communication sans fil, le rendement énergétique est un critère primordial qui impacte la durée d’utilisation de la batterie. Principalement déterminé par la consommation d’énergie du transmetteur, il est plus particulièrement lié à celle de l’amplificateur de puissance (PA). Pour les terminaux mobiles de 4ème génération (4G), les techniques de transmission et les modulations utilisées pour atteindre les débits de données visés induisant une dynamique importante du signal à transmettre, l’implémentation de techniques d’amélioration du rendement autour du PA devient indispensable, afin de le reconfigurer en puissance.Nous avons mis au point dans ce travail de recherche des architectures innovantes utilisant les techniques d’amélioration du Power Cell Switching (PCS) et de l’Envelope Tracking (ET). Le double objectif visé étant d’améliorer significativement le rendement pour les faibles niveaux de puissance et d’apporter de la flexibilité par rapport à un PA utilisé seul. Une première architecture utilisant la technique du PCS totalement intégré en technologie CMOS 65nm de STMicroelectronics, mettant en œuvre des transformateurs comme combineurs de puissance, a été réalisée pour valider la fonctionnalité du concept proposé. Puis une deuxième architecture combinant les techniques du PCS et de l’ET a été conçue, afin d’évaluer les avantages qu’apporte la combinaison de ces deux techniques par rapport à un PA fonctionnant seul et à un PA développé utilisant la technique du PCS
This thesis deals with the design of reconfigurable power amplifiers implemented in CMOS technology for 4G LTE application. For the next generation communication systems such as 4G LTE, orthogonal frequency division multiplexing (OFDM) is employed for a wideband communication. Indeed, signal information is encoded both in amplitude and phase domains, which results in a higher peak to average power ratio than for 2G and 3G systems. Consequently, the overall power amplifier (PA) efficiency does not only depend on efficiency at maximum power, but also and mainly on efficiency at back-off level where the PA operates most of the time. Obviously, classical PA architectures do not address this problem, because it can only achieve maximum efficiency at a single power level, usually around the peak output power. Therefore, the overall efficiency of the PA is considerably low and efficiency improvement techniques are required to increase the battery life-time. This thesis exposes innovative architectures using Power Cell Switching (PCS) and Envelope Tracking (ET) techniques. The main objective of the proposed architectures is to significantly improve the average efficiency in comparison with a stand-alone power amplifier at power back-off. Consequently, a reconfigurable PA architecture using a 4-step PCS technique has been implemented in CMOS 65nm technology. A second architecture was designed to evaluate the improvement obtained with the combination of these two techniques

Mestrado em Engenharia Eletrónica e Telecomunicações
The theme of this dissertation work is focused in one of the key technologies specified in the last 4G cellular standards, which are the MIMO systems. In this context, the MIMO (Multiple Input Multiple Output) acronym is used to define a communication system where multiple antennas are used, therefore using this type of systems jointly with specific signal processing techniques, we can use the spatial dimension in order to generate multiplexing, diversity and beamforming gains. The aim of this work is to show the type of signal processing techniques that must be applied in order to achieve the gains referenced above, as well the optimal channel conditions in which these gains are maximized.Therefore, beyond the presentation of the theoretical background related with these type of techniques, we will present the MIMO transmission modes specified on 4G-LTE, having not only the aiming of show the type of practical constraints verified in a practical implementation, but also present the solutions used to solve that kind of constraints. In the last part of this work is presented a simulation platform implemented for one of the spatial multiplexing modes specified on LTE, which is the mode 4. The numerical results obtained allowed to see the advantage in the use of SIC (Successive Interference Cancelation) equalizers for multi-layer transmission modes, as well as the performance limitations related with the transmission through a channel where high spatial correlation conditions are verified. With the use of multiple precoding matrices, we understand the importance of perform a correct precoding selection in order to improve the transmission through a channel with this type of conditions.Beyond the observations referred above, we also saw the diversity cost related with the increase of spatial multiplexing gain.
O tema deste trabalho de dissertação visa uma das tecnologias chave especificada nos últimos standards 4G para o sector das comunicações móveis, que são os sistemas MIMO. Neste contexto, o acrónimo MIMO é usado para referenciar um sistema de comunicação que faz uso de múltiplas antenas, assim, usando este tipo de sistemas conjuntamente com técnicas de processamento de sinal apropriadas, podemos usar a dimensão espacial de forma a gerar ganhos de multiplexagem, diversidade e beamforming. O objetivo deste trabalho é mostrar que tipo de processamento de sinal deve ser feito de forma a gerar cada um dos ganhos acima referidos, assim como as condições de canal em que estes podem ser maximizados. Para além da apresentação dos fundamentos teóricos relacionados com este tipo de técnicas, iremos apresentar os modos de transmissão MIMO especificados para o 4GLTE, tendo não só como objectivo observar o tipo de constrangimentos prácticos inerentes a uma implementação real, mas também observar o tipo de soluções usadas para fazer face a esses mesmos constrangimentos. Na parte final do trabalho é apresentada uma plataforma de simulação implementada para um dos modos de multiplexagem espacial especificados no LTE, ou seja o modo 4. Os resultados numéricos obtidos permitiram constatar a vantagem em usar equalizadores SIC em modos de transmissão multi-camada, assim como também nos permitiu observar as limitações de performance inerentes á transmissão através de um canal com elevada correlação espacial. Usando várias matrizes de pré-codificação especificadas no LTE para este modo, conseguimos perceber a importância que a escolha de uma correcta précodificação tem no melhoramento de desempenho da transmissão neste tipo de canais. Para além das observações referidas acima, também podemos verificar o custo em termos de diversidade inerente ao aumento do ganho de multiplexagem.

L'explosion du trafic dans les réseaux mobiles d'aujourd'hui est l'une des préoccupations majeures des opérateurs mobiles. En effet, entre investir dans le développement de l’infrastructure pour supporter l’évolution des besoins des utilisateurs et faire face à la concurrence accrue des nouveaux acteurs du marché, l’enjeu est considérable. Dans ce contexte, les communications Device-to-Device (D2D) offrent aux opérateurs mobiles de nouvelles opportunités aussi bien financières que techniques, à travers les communications directes entre les appareils mobiles permettant de délester le réseau d'une partie du trafic. L'organisme de standardisation 3GPP a défini des évolutions de son architecture LTE/4G fonctionnelle pour supporter les communications D2D dans le cadre de Services de Proximité (ProSe). Cependant, les modèles économiques autour de ces nouveaux services sont encore flous et les solutions actuellement proposées par le 3GPP visent un déploiement à court terme d’un ensemble limité de services (ex : les services de sécurité publique). La première contribution proposée dans le cadre de cette thèse est une évolution de l'architecture ProSe vers une architecture cible distribuée dans laquelle les fonctions liées à ProSe sont mutualisées avec d'autres fonctions réseaux. La deuxième contribution porte sur l’intégration des services véhiculaires dans les réseaux mobiles en tant que services ProSe particuliers reposant sur les communications D2D. L'architecture CVS (Cellular Vehicular Services) est alors proposée comme solution pour un déploiement à grande échelle des services véhiculaires en s'appuyant sur une nouvelle évolution de l’architecture ProSe distribuée. Un algorithme de « clustering » ainsi que des procédures de communication en mode relais D2D sont utilisés dans la conception de la solution afin d’optimiser l'usage des ressources du réseau. Enfin, les performances de ces contributions sont évaluées à l'aide de modèles analytiques et de simulations afin de valider les approches et solutions proposées
The traffic explosion in today’s mobile networks is one of the major concerns of mobile operators. This explosion is mostly widening the gap between networks’ capacities and users’ growing needs in terms of bandwidth and QoS (Quality of Service), which directly impacts operators’ business profitability. In this context, Device-to-Device (D2D) communications offer mobile operators business and technical opportunities by allowing the network traffic offload with D2D direct communications between mobile devices. The recent standardization of D2D-based services as Proximity Services (ProSe) by the 3GPP provides already a set of enhancements to the current LTE/4G architecture to support these services. However, still in its infancy, the proposed solutions are envisioned for short-term market deployments and for a limited set of service categories (i.e public safety services). As a first contribution of this thesis, the proposed Distributed ProSe Architecture enhances the current ProSe architecture for a longer term deployment perspective of D2D-based services. On the basis of this enhanced architecture, vehicular communications and related services are further investigated as a specific implementation of ProSe as well as a new market opportunity for mobile operators. The CVS (Cellular Vehicular Services) solution is then introduced as an architecture framework that enables the integration of vehicular networks into mobile operators’ network infrastructure. A mobile network clustering algorithm and D2D relay-based communication mechanisms are used in the solution design in order to optimize the use of both core and radio network resources. Performance evaluation through analytical modeling and simulations are also carried out to validate the proposed contributions

One of the challenges of the mobile industry is to cope with the growth of mobile traffic demand expected for the next years, primarily driven by the increasing usage of mobile video services. Indeed, the existence of increasingly powerful terminals is encouraging the consumption of high-quality video content. Usually, video services are identified with linear Television (TV) and scheduled broadcast (point-to-multipoint (p-t-m)) distribution. However, the consumption of video content over mobile networks is different from traditional fixed TV because contents are mainly consumed on-demand with unicast point-to-point (p-t-p) connections. Then, the convergence of linear TV and on-demand content delivery represents a challenge that requires a combined broadcast/unicast transmission model. This dissertation addresses the use of broadcasting technologies for the provision of mobile multimedia services in Fourth Generation (4G) mobile broadband networks and beyond. Specifically, the dissertation focuses on the broadcast technology included in 4G Long Term Evolution (LTE) and LTE Advanced (LTE-A) networks, known as Enhanced Multicast Broadcast Multimedia Services (eMBMS). It analyses the benefits of the eMBMS physical layer aspects regarding Multimedia Broadcast Multicast Services over a Single Frequency Network (MBSFN) deployments and identifies the current limitations of eMBMS at physical layer by comparing with the broadcast technology of the other 4G mobile system, the Institute of Electrical and Electronics Engineers (IEEE) 802.16m standard. Those limitations are the use of a dedicated carrier and Multiple-Input Multiple-Output (MIMO) techniques for broadcast transmissions. Our investigations employ a complete simulation platform including link-level and system-level simulations to evaluate the performance of broadcast transmissions in these real technologies. The research on eMBMS services is aimed at finding the optimum delivery of streaming and file download services focusing on the Radio Resource Management (RRM) problem and trade-off between Physical layer – Forward Error Correction (PHY-FEC) and Application Layer - Forward Error Correction (AL-FEC). Concerning streaming services, results show that the use of AL-FEC increases the coverage level and, then, the maximum service data rate. The gain due to AL-FEC is greater in scenarios with high mobility users, although, this gain is limited if low zapping times are desired. Regarding file delivery services, this dissertation analyses the duration of the transmission required to guarantee the correct file reception and the reduction in the mean throughput of unicast users with different delivery modes. They are the unicast delivery, the eMBMS delivery and a hybrid approach, which combines a first eMBMS delivery with a postdelivery error repair phase with unicast transmissions. Our results show that the hybrid delivery is the most efficient configuration in terms of file download time, although it further reduces unicast performance.
Calabuig Gaspar, J. (2015). Broadcasting in 4G mobile broadband networks and its evolution towards 5G [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/48561
TESIS

Actualmente, más de la mitad de habitantes de nuestro país: 15,4 millones de peruanos, son usuarios de Internet móvil, lo que nos demuestra que estamos frente ante un servicio prioritario para la mayoría de la población, que nos permite el revisar el correo desde el celular, actualizar las redes sociales en cualquier momento, descargar música o ver videos ya no son actividades propias de tres de cada diez ciudadanos, sino que en un año pasamos a 51% de penetración y dentro de cuatro años serán siete de cada 10 los internautas móviles y tres de ellos, según Cisco, usarán redes 4G LTE. Las conexiones vía 4G LTE hoy son usadas por aproximadamente cuatro millones de peruanos, los costos de los equipos y los planes de datos que la ofrecen suelen ser un poco más elevados que las generaciones anteriores (3G o 2G), sin embargo, su tendencia para ser adquirida es imparable gracias a que se trata de una tecnología idónea en términos de velocidad de transmisión de datos que genera navegar en Internet, según explica el catedrático de la UPC, Carlos Valdez. Por lo que señalo como un obstáculo en estos momentos, la deficiente infraestructura para soportar la gran demanda de los usuarios, la no existencia de un plan de inversiones que nos permita contar con un servicio adecuado en los próximos años, si sigue creciendo el número de usuarios y los avances de uso de esta tecnología 4G sobretodo en los lugares más alejados de la Región Junín.

El presente proyecto de tesis consiste en realizar el diseño de una red 4G-LTE INDOOR para el centro comercial Real Plaza Santa Clara con los objetivos de mejorar la cobertura celular y aumentar la velocidad de acceso a internet móvil; con ello, se busca ofrecer un mejor servicio móvil que se traducirá en ganancias. Se usa la solución indoor de un sistema pasivo distribuido de antenas (DAS) para su desarrollo. Se tienen en cuenta: el cumplimiento de los KPI de LTE; las posibilidades de implementación en las zonas elegidas para el despliegue; que los resultados finales del diseño sean los deseados y analizar si el proyecto es rentable. La tesis está dividida en 4 capítulos que se presentan a continuación. El primer capítulo desarrolla el marco teórico de la tecnología 4G LTE y las soluciones indoor explicando los detalles más importantes para el desarrollo del diseño. El segundo capítulo está centrado en el análisis de la problemática de cobertura aplicando parte de la metodología del proyecto previo al desarrollo del diseño. El tercer capítulo presenta la ingeniería de diseño tomando en consideración lo necesario para un desarrollo óptimo; además, muestra simulaciones de cobertura en software como también resultados finales reales post-instalación. El cuarto capítulo, por su parte, describe el análisis económico del proyecto; así como, la evaluación de rentabilidad del mismo. Por último, se presentan las conclusiones y recomendaciones del presente proyecto. Se proponen algunos trabajos que permitan tener una visión más amplia de lo que significa desplegar una red indoor y su proyección a futuro.
Tesis

Femtocells are seen to be the future of Long Term Evaluation (LTE) networks to improve the performance of indoor, outdoor and cell edge User Equipments (UEs). These small cells work efficiently in areas that suffer from high penetration loss and path-loss to improve the coverage area. It is said that 30% of total served UEs in LTE networks are vehicular, which poses challenges in LTE networks due to their high mobility, high vehicular penetration loss (VPL), high path loss and high interference. Therefore, self-optimising and dynamic solutions are required to incorporate more intelligence into the current standard of LTE system. This makes the network more adaptive, able to handle peak data demands and cope with the increasing capacity for vehicular UEs. This research has drawn a performance comparison between vehicular UEs who are served by Mobile-Femto, Fixed-Femto and eNB under different VPL scales that range between highs and lows e.g. 0dB, 25dB and 40dB. Deploying Mobile-Femto under high VPLs has improved the vehicular UE Ergodic capacity by 1% and 5% under 25dB and 40dB VPL respectively as compared to other eNB technologies. A noticeable improvement is also seen in signal strength, throughput and spectral efficiency. Furthermore, this research discusses the co-channel interference between the eNB and the Mobile-Femto as both share the same resources and bandwidth. This has created an interference issue from the downlink signals of each other to their UEs. There were no previous solutions that worked efficiently in cases where UEs and base stations are mobile. Therefore, this research has adapted an efficient frequency reuse scheme that worked dynamically over distance and achieved improved results in the signal strength and throughput of Macro and Mobile-Femto UE as compared to previous interference management schemes e.g. Fractional Frequency Reuse factor1 (NoFFR-3) and Fractional Frequency Reuse factor3 (FFR-3). Also, the achieved results show that implementing the proposed handover scheme together with the Mobile-Femto deployment has reduced the dropped calls probability by 7% and the blocked calls probability by 14% compared to the direct transmission from the eNB. Furthermore, the outage signal probabilities under different VPLs have been reduced by 1.8% and 2% when the VPLs are 25dB and 40dB respectively compared to other eNB technologies.

The dissertation concerns about the path loss calculation of Radio Frequency (RF) propagation models for 4G Long Term Evolution (LTE) Network to prefer the best Radio Frequency propagation model. The radio propagation models are very significant while planning of any wireless communication system. A comparative analysis between radio propagation models e.g. SUI model, Okumura model, Cost 231 Hata Model, Cost 231-Walfisch Ikegami and Ericsson 9999 model that would be used for outdoor propagation in LTE. The comparison and performance analysis has been made by using different geological environments e.g. urban, sub-urban and rural areas. The simulation scenario is made to calculate the lowest path loss in above defined environments by using selected frequency and height of base station antennas while keeping a constant distance between the transmitter and receiver antennas.
Asad Saeed C/O Muhammad Awais Hovslagargatan 47 LGH 1004 19431 Stockholm Sweden Mob: 0046723333734

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.

Avec l’arrivée de la 5G NR, les architectures des émetteurs-récepteurs des terminaux mobiles doivent intégrer plus de composants (filtres, amplificateurs de puissance…) afin d’adresser des bandes plus nombreuses et plus larges (notamment les bandes « sub-6 GHz ») en plus de traiter des signaux plus complexes. Ces nouvelles contraintes d’encombrement et de performances auxquelles doivent répondre les émetteurs-récepteurs ont un impact direct sur les spécifications techniques des amplificateurs de puissance (PA). D’une part il est nécessaire d’avoir des PA qui adressent des bandes plus larges afin de réduire le nombre de composants dans la chaîne d’émission ; d’autre part, ces PA doivent répondre aux critères de linéarité des nouveaux standards (LTE-A et 5G NR) tout en assurant une bonne efficacité énergétique de fonctionnement. Les travaux de cette thèse portent sur l’investigation d’architectures avancées de PA alliant largeur de bande, linéarité et efficacité énergétique.Le contexte et les motivations de la thèse énoncés, le choix de la technologie RF SOI 130nm et les contraintes auxquels doit répondre le PA sont justifiés. Une étude de l’état de l’art des architectures avancées (à efficacité améliorée) de PA permet de retenir l’architecture Doherty comme solution intéressante. Une étude théorique de l’architecture Doherty est effectuée afin de modéliser son fonctionnement, d’identifier l’impact des paramètres de dimensionnement et des capacités parasites du transistor sur les performances de celle-ci avant d’explorer les perspectives qu’elle présente en termes de largeur de bande. Un premier circuit démonstrateur a été implémenté en RF SOI 130nm. Il s’agit d’un étage amplificateur Doherty couvrant la bande 3,2-3,6 GHz. Pour un signal LTE 10MHz 50RB à une puissance de sortie de 27dBm, un ACLR maximal de -30,5 dBc et une PAE minimale de 36% a été mesurée sur toute la bande. Un deuxième circuit Doherty intégrant un étage de pré-amplification (driver) a été implémenté dans la même technologie. Les mesures pour un signal LTE 10MHz 12RB à 28 dBm de puissance de sortie donnent un ACLR maximal de -35 dBc et une PAE minimale de 32% sur toute la bande 3,2-3,8 GHz ce qui permet de couvrir les bandes B42, B43 et B49
The arrival of the 5G NR put more constraints on the transceivers architectures. They must integrate more components (filters, power amplifiers, etc.) in order to address more numerous and wider bands (in particular the “sub-6 GHz” bands) in addition to processing more complex signals. These new space and performance constraints that transceivers must meet have a direct impact on the technical specifications of power amplifiers (PAs). On the one hand it is necessary to have PAs which address wider bands in order to reduce the number of components in the emission chain; on the other hand, these PAs must meet the criteria of linearity of the new standards (LTE-A and 5G NR) while ensuring good operating energy efficiency. The work of this thesis concerns the investigation of advanced PA architectures combining bandwidth, linearity and energy efficiency.The context and the motivations of the thesis stated, the choice of SOI 130nm RF technology and the constraints to which the PA must respond are justified. A study of the state of the art of improved efficiency PAs architectures makes it possible to select Doherty architecture as an interesting solution. A theoretical study of the Doherty architecture is carried out in order to model its operation, to identify the impact of the dimensioning parameters and the parasitic capacitances of the transistor on the performances before exploring the bandwidth perspectives it presents. A first demonstrator circuit was implemented in RF SOI 130nm. It is a Doherty amplifier stage covering the 3.2-3.6 GHz band. For an LTE 10MHz 50RB signal at an output power of 27dBm, a maximum ACLR of -30.5 dBc and a minimum PAE of 36% was measured across the band. A second Doherty circuit integrating a driver stage has been implemented in the same technology. Measurements for an LTE 10MHz 12RB signal at 28 dBm of output power give a maximum ACLR of -35 dBc and a minimum PAE of 32% over the whole band 3.2-3.8 GHz which allows to cover the B42, B43 and B49 bands

Ingeniero Civil Eléctrico
Entel S.A., la mayor empresa de telecomunicaciones móviles de Chile, requería evaluar el impacto que tendría la incorporación del servicio Voice Over LTE (VoLTE) en su red 4G de datos, en Santiago, con el fin de estimar la inversión requerida en caso de que existiera disminución de cobertura del servicio. Dado lo anterior, el objetivo del presente trabajo de título se enfocó en determinar el área de cobertura que tendrá la actual red 4G de Entel al incorporar el servicio VoLTE. Para llevar a cabo esta tarea se diseñó un Link Budget de VoLTE, el cual se utilizó posteriormente para determinar los puntos de corte en simulaciones que se realizaron en el programa Mentum Planet. De esta forma, se comparó la cobertura de la red de datos (Best Effort) con la cobertura VoLTE. La metodología utilizada en el desarrollo de la presente memoria comprendió la investigación y el análisis de redes móviles LTE, desarrollando y plasmando en el segundo capítulo, una base teórica que permite un amplio y fácil entendimiento de éstas para cualquier persona. Posteriormente, comprendió el diseñó del Link Budget de VoLTE, el cuál fue generado en un documento Excel, otorgando de esta forma una herramienta sencilla y útil al área de optimización de redes de acceso de Entel. El trabajo concluyó con la realización de sets de simulaciones en el programa solicitado, con lo que se obtuvo los porcentajes de cobertura asociados tanto a la red Best Effort como al servicio VoLTE, para las bandas de frecuencia de 2600 MHz y 700 MHz. Entre los principales resultados del presente trabajo, cabe destacar: 1. Disminución aproximada de un 7.5% de cobertura para el servicio VoLTE en comparación a la cobertura del servicio de datos Fourth Generation of Wireless Telephone Technology (4G), para la banda 2600 MHz, considerando Reference Signal Received Power (RSRP) de corte sin fading. 2. Disminución aproximada de un 19% de cobertura para el servicio VoLTE en comparación a la cobertura del servicio de datos 4G, para la banda 700 MHz, considerando RSRP de corte sin fading. 3. Se confirma la importancia del feature TTI Bundling para mejorar la cobertura del enlace ascendente, estableciendo una mejora entre un 20 y un 25% en la cobertura. Como consecuencia final, el presente trabajo entrega a Entel una cuantificación de la cobertura esperada, así como un conjunto de recomendaciones para la implementación del servicio VoLTE, y de ésta forma, pasar a la etapa de evaluación económica para la implementación definitiva del proyecto.

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

Context. The single blackboard architecture is widely used in the LTE application area. Despite its several benefits, this architecture limits synchronization possibilities of the developed systems and increases the signal operational latency. As a result the DSP (Digital Signal Processing) utilization is suboptimal. Objectives. In this thesis, we design a new architecture, which combines concepts of Multi-Blackboards and Pipes & Filters architectures, as a replacement for the current single blackboard architecture at Ericsson. The implementation of the new architecture makes the environment asynchronous. We evaluate the new architecture at simulated environment of Ericsson with 222225 connection items from 9000 base stations all over the world. Each connection item has a complete UE session and one of possible connection statuses, e.g. active, inactive, connected, DRX sleeping, postponed. These connection items can be from any country in the world. Methods. We design a new architecture for UPCUL component of LTE network based on analysis of real network data from Ericsson. We perform a case study to develop and evaluate the new architecture at Ericsson. Results. We evaluate the new architecture by performing a case study at Ericsson. The results of case study show that the new architecture not only increases DSP utilization by 35%, but also decreases signal operational latency by 53%, FO operation time by 20% and FO operation cycles by 20%. Also, the new architecture increases correctness performance. Conclusions.  We conclude that the new architecture increases DSP utilization and decreases the signal operational latency, therefore, improves performances of UPCUL component of LTE.  Due to time constraints, we only considered four LTE FOs (Function Objects) and relative signals. Future work should focus mainly on the other FOs and signals. We also analyze unconsidered FOs, and make an integration solution table which contains solutions to integrate these unconsidered FOs into the new architecture.  The second avenue for future work is to re-size the size of the two blackboard storages. We find out that the maximum memory size of needed UE sessions per sub-frame is only 1.305% of the memory size of all UE sessions (31650 bytes). So the memory size of blackboard storage should be adjusted on the basis of needed UE sessions instead of all UE sessions.

Le problème de coloration de graphe est un problème NP-complet particulièrement étudié, qui permet de modéliser de problèmes dans des domaines variés. Dans cette thèse, de nouveaux algorithmes exacts basés sur une étude de la structure du graphe sont proposés. Ce travail s'appuie sur l'algorithme « Total solutions Exact graph Coloring » (TexaCol) qui construit toutes les solutions en exploitant l'ensemble des cliques d'un graphe. Deux algorithmes exacts, « Partial best solutions Exact graph Coloring » (PexaCol) et « All best solutions Exact graph Coloring » (AexaCol), sont présentés ici pour construire certaines solutions optimales ou toutes les meilleures solutions. Ces deux algorithmes utilisent la méthode de backtracking, dans laquelle ils ne choisissent que les sous-ensembles de meilleurs solutions pour continuer la coloration. L’analyse de résultat montre que PexaCol et AexaCol sont capables de traiter des graphes plus grands que TexaCol. Mais surtout, AexaCol trouve toutes les meilleures solutions significativement plus vite que TexaCol ainsi que le solveur Gurobi, qui sont utilisés comme référence.La téléphonie mobile est un domaine en plein essor qui peut s'appuyer sur une modélisation à base de graphes. Actuellement, les techniques de type « Device-to-Device » (D2D) prennent une place importante dans les réseaux mobiles. L’allocation de ressource constitue l'un des principaux problèmes en matière de performance. Pour assigner efficacement une ressource radio à une paire D2D dans le système Long-Term Evolution (LTE), un schéma systématique d'allocation de ressources est proposé dans cette thèse. Il est basé sur une clusturisation des liens D2D, et permet de prendre en compte à la fois l'allocation inter-cluster et intra-cluster des ressources. En déterminant les zones d'interférence, le problème d'allocation des ressources inter-cluster est formulé comme un problème de coloration de graphe dynamique. Un algorithme de coloration de graphe dynamique est ainsi proposé, basé sur PexaCol. Cet algorithme peut assigner les ressources radio aux clusters qui sont générés ou supprimés dynamiquement. L’analyse numérique montre que cet algorithme assure une bonne performance en termes d'utilisation des ressources, de temps d’exécution et d'adaptabilité. Concernant le problème d’allocation de ressources inter-cluster, une méthode fondée sur la topologie est proposée, intégrant naturellement l'allocation de puissance et l’allocation de Resource Block (RB). Pour simplifier ce problème d'allocation de ressources, la meilleure topologie est choisie à chaque étape, celle qui permet d'obtenir le meilleur débit en utilisant le moins de RBs. A partir de ce procédé, quatre algorithmes d'optimisation sont proposés: l’algorithme glouton statique, PexaCol statique, PexaCol dynamique et PexaCol dynamique approximatif. L'analyse des résultats montre que pour les petits clusters, les versions statiques et dynamiques de PexaCol permettent d'obtenir un index d’optimisation maximal en choisissant la meilleure topologie locale pour chaque noeud. A l'opposé, les algorithmes "glouton statique" et "PexaCol dynamique approximatif" permettent d'obtenir une solution sous-optimale pour l'optimisation locale avec une complexité moindre. Pour les grands clusters, avec certaine séquence de la coloration, le PexaCol dynamique approximatif est mieux que l’algorithme glouton statique pour l’index d’optimisation pendant un temps d’exécution acceptable
Graph coloring problem is a famous NP-complete problem, which has extensive applications. In the thesis, new exact graph coloring algorithms are researched from a graph structure point of view. Based on Total solutions Exact graph Coloring algorithm (TexaCol) which is capable of getting all coloring solution subsets for each subgraph, two other exact algorithms, Partial best solutions Exact graph Coloring algorithm (PexaCol) and All best solutions Exact graph Coloring algorithm (AexaCol), are presented to get multiple best solutions. These two algorithms utilize the backtracking method, in which they only choose the best solution subset each step to continue the coloring until partial or all best solutions are obtained. The result analysis shows that PexaCol and AexaCol can deal with larger graphs than TexaCol and especially, AexaCol runs much faster than TexaCol and the solver Gurobi to get all best solutions.Device-to-Device (D2D) is a promising technique for the future mobile networks, such as 5th generation wireless systems (5G), and the resource allocation is one of the most crucial problems for its performance. In order to efficiently allocate radio resource for D2D links in Long-Term Evolution (LTE) system, a systematic resource allocation scheme is proposed based on D2D clusters, including the inter-cluster resource allocation and the intra-cluster resource allocation. With the cluster interference range, the inter-cluster resource allocation problem is formulated as a dynamic graph coloring problem, and a dynamic graph coloring algorithm is designed based on PexaCol. This algorithm is able to allocate radio resource to clusters while they are dynamically generated and deleted. The numerical analysis results show that this algorithm has good performance in resource utilization, runtime and scalability.For the intra-cluster resource allocation problem, a topology-based resource allocation method is designed naturally combining power allocation with Resource Block (RB) allocation. To simplify this associated optimization problem, a local optimal method is proposed, in which the best topology is chosen each step achieving the maximal throughput with the minimum number of assigned RBs. With respect to this method, four algorithms are presented: static greedy, static PexaCol, dynamic PexaCol and dynamic PexaCol approximate. Result analysis shows that for small-scale clusters, static PexaCol and dynamic PexaCol are capable of getting a maximal optimization index by locally choosing the best topology for each node while static greedy and dynamic PexaCol approximate are able to get the suboptimal solution for the local optimization with much lower complexity. For large-scale clusters, giving certain treating sequences, the dynamic PexaCol approximate performs better than static greedy regarding the optimization index within an acceptable runtime

[EN] In today's information society, there is a growing need to access data communication services ubiquitously, with mobility and increasingly higher data rates. This society's demand has motivated the development of the fourth generation of mobile communications (4G) and its evolution towards the fifth generation (5G). This development has required a revolution on the radio interface of the mobile communications systems, and, consequently, has significantly modified their capabilities and their radio resource management. This is the case of the technology known as Long Term Evolution (LTE) and its 4G version called LTE-Advanced. This Doctoral Thesis addresses the modelling, the radio resource management analysis, and the performance evaluation of the downlink of LTE and LTE-Advanced where, among the different features of LTE-Advanced, the focus is on the Coordinated Multi-Point (CoMP) transmission. The Thesis provides a detailed description of the main characteristics of LTE and LTE-Advanced. The high complexity of these systems, has prompted the use of computer simulations as the primary research methodology. The Thesis makes a detailed description of the simulation methodology and the system modelling required, including some contributions of the author in this field. Among them, it is of significant relevance the link-level simulation results used in the European project WINNER + for the LTE evaluation. With regard to the analysis of the radio resource management in LTE, the fundamentals of link adaptation and scheduling are explained in the first place. In relation to the scheduling, the Thesis includes a thorough study of the proportional fairness concept and the suboptimal implementation typically used in LTE to maximize this metric. This study has resulted in a series of ideas embodied in a modification of the typical implementation, which has proved to be capable of increasing the proportional fairness of the resource allocations. Moreover, the link adaptation analysis has revealed the "flash-light" effect problem, which is characterized by a high interference variability due to rapid changes in the scheduling decisions. The Thesis demonstrates that a particular implementation that stabilizes the scheduling decisions can improve the system performance. The radio resource management analysis of this Thesis is completed with the study of CoMP. Specifically, the CoMP scheme studied in this Thesis is a solution with coordinated scheduling and beamforming (CS/CB), that takes into account realistic and robust assumptions concerning the knowledge that the coordinated points have about the channel state. The Thesis proposes this solution for its simplicity and its ability to improve high data rates coverage and capacity even with incomplete channel knowledge. Concerning LTE and LTE-Advanced evaluation, it is performed in two different types of scenarios. On the one hand, the scenarios defined in the process of evaluation of IMT-Advanced. In this framework, it is evaluated the importance of different multi-antenna techniques, including CoMP, considering full-buffer traffic models. The most important conclusions in these scenarios are the significant performance improvement achieved with spatial multiplexing of users and the fact that CoMP mechanisms provide a reduced benefit. The second group of scenarios are those defined by the European project METIS for the evaluation of 5G technologies. Specifically, an indoor office scenario and an outdoor sports stadium have been selected. In these scenarios, a realistic traffic model is used, and it has been demonstrated the utility of CoMP to satisfy the first 5G requirement definitions with feasible frequency bandwidths. In these scenarios with less homogeneous deployments, or with a limited number of transmitters originating the major part of interference, is where this Thesis has found CoMP to be more useful and where the Thesis promotes its use.
[ES] En la actual sociedad, hay una creciente necesidad de acceso a servicios de comunicación de datos de forma ubicua, móvil y a velocidades cada vez más altas. Esta demanda ha motivado el desarrollo de la cuarta generación de comunicaciones móviles (4G) y su evolución hacia la quinta generación (5G). Este desarrollo ha requerido una revolución en la interfaz radio de los sistemas de comunicaciones móviles modificando en gran medida sus capacidades y la forma en la que se gestionan sus recursos. Este es el caso de la tecnología conocida como Long Term Evolution (LTE) y su versión 4G llamada LTE-Advanced. En concreto, esta Tesis Doctoral aborda el modelado, análisis de la gestión de recursos radio y evaluación de prestaciones del enlace descendente de LTE y LTE-Advanced, donde, de entre las características de LTE-Advanced, se ha puesto el foco de atención en la transmisión multipunto coordinada (CoMP). La Tesis proporciona una descripción detallada de las principales características de LTE y LTE-Advanced. La gran complejidad del sistema descrito ha motivado que la metodología de estudio haya sido la simulación mediante ordenador. La Tesis realiza una descripción detallada de dicha metodología y del modelado del sistema empleado, incluyendo algunas aportaciones del autor en este campo. De entre éstas, destaca la provisión de resultados de simulación de nivel de enlace que se usaron en el proyecto europeo WINNER+ para la evaluación de LTE. En cuanto al análisis de la gestión de recursos radio en LTE, en primer lugar, se explican los fundamentos de la adaptación al enlace y el scheduling. En relación con el scheduling, se realiza un estudio del concepto de proportional fairness y de la implementación subóptima típicamente usada en LTE para maximizar esta métrica. Este estudio ha dado como resultado una modificación de la implementación típica que ha demostrado ser capaz de aumentar la proportional fairness en la asignación de recursos con un bajo incremento de complejidad. Además, el análisis de la adaptación al enlace ha revelado el problema del efecto de "luz de flash" consistente en la alta variabilidad de la interferencia debida a rápidos cambios en las decisiones del scheduler. La Tesis demuestra que se pueden mejorar las prestaciones del sistema estabilizando dichas decisiones mediante una implementación concreta. El bloque de análisis de la gestión de recursos se completa con el estudio de CoMP. Específicamente, se estudia una solución con coordinación de scheduling y conformación de haz (CS/CB) que tiene en cuenta suposiciones reales y robustas en cuanto al conocimiento que los puntos coordinados tienen de los canales radio. La Tesis propone esta solución por su sencillez y capacidad de mejorar la eficiencia de los sistemas de comunicaciones móviles, tanto en cobertura de velocidades altas de transmisión como en capacidad, aun teniendo un conocimiento incompleto del canal. En cuanto a la evaluación de LTE y LTE-Advanced, ésta se realiza en dos tipos de escenarios. Por un lado, los escenarios definidos en el proceso de evaluación de IMT-Advanced. En este marco, se evalúa la importancia de diferentes técnicas de transmisión multiantena, incluyendo CoMP, y considerando tráfico de tipo full-buffer. Se ha obtenido una gran mejora de prestaciones por la multiplexación espacial de usuarios y mejoras discretas por el uso de CoMP. El segundo grupo de escenarios son los definidos por el proyecto europeo METIS para evaluación de tecnologías 5G, concretamente se han elegido un escenario de interiores con una oficina, y uno de exteriores con un estadio deportivo. En estos escenarios se utiliza un tráfico realista y se ha demostrado la utilidad de CoMP para mejorar las prestaciones del sistema. En estos escenarios con despliegues menos uniformes, o con un número limitado de transmisores provocando la mayor parte de la interferencia, es donde esta Tesis ha encontrado la mayor u
[CAT] En l'actual societat de la informació, hi ha una creixent necessitat d'accés a serveis de comunicació de dades de forma ubiqua, mòbil i a velocitats cada vegada més altes. Aquesta demanda de la societat, ha motivat el desenrotllament de la quarta generació de comunicacions mòbils (4G) i la seua evolució cap a la quinta generació (5G). Aquest desenrotllament ha requerit una revolució en la interfície ràdio dels sistemes de comunicacions mòbils i ha modificat en gran manera les seues capacitats i la forma en què es gestionen els seus recursos. Aquest és el cas de la tecnologia coneguda com a Long Term Evolution (LTE) i la seua versió 4G anomenada LTE-Advanced. En concret, aquesta Tesi Doctoral aborda el modelatge, anàlisi de la gestió de recursos ràdio i avaluació de prestacions de l'enllaç descendent de LTE i LTE-Advanced, on, d'entre les característiques de LTE-Advanced, s'ha posat el centre d'atenció en la transmissió multipunt coordinada (CoMP). La Tesi proporciona una descripció detallada de les principals característiques de LTE i LTE-Advanced. La gran complexitat del sistema descrit ha motivat que la metodologia d'estudi s'haja basat en simulació per mitjà d'ordinador. La Tesi realitza una descripció detallada de la metodologia de simulació i del modelatge del sistema empleat, incloent-hi algunes aportacions de l'autor en aquest camp. D'entre aquestes, destaca la provisió de resultats de simulació de nivell d'enllaç que es van usar en el projecte europeu WINNER+ per a l'avaluació de LTE. Pel que fa a l'anàlisi de la gestió de recursos ràdio en LTE, en primer lloc, s'expliquen els fonaments de l'adaptació a l'enllaç i el scheduling. En relació amb el scheduling, es realitza un estudi del concepte de proportional fairness i de la implementació subòptima típicament usada en LTE per a maximitzar aquesta mètrica. L'estudi ha donat com a resultat una modificació de la implementació típica que ha demostrat ser capaç d'augmentar la proportional fairness en l'assignació de recursos amb un baix increment de complexitat. A més, l'anàlisi de l'adaptació a l'enllaç ha desvetllat el problema de l'efecte de "llum de flaix" consistent en la alta variabilitat de la interferència deguda a una ràpida variació de les assignacions de recursos. La Tesi demostra que es poden millorar les prestacions del sistema estabilitzant les decisions del scheduler mitjançant una implementació concreta. En el bloc d'anàlisi de la gestió de recursos d'aquesta Tesi es completa amb l'estudi de CoMP. Específicament, s'estudia una solució amb coordinació de scheduling i conformació de feix (CS/CB), que té en compte suposicions reals i robustes quant al coneixement que els punts coordinats tenen dels canals ràdio dels usuaris servits. La Tesi proposa aquesta solució per la seua senzillesa i capacitat de millorar l'eficiència dels sistemes de comunicacions mòbils, tant en cobertura de velocitats altes de transmissió com en capacitat, encara tenint un coneixement incomplet del canal. Quant a l'avaluació de LTE i LTE-Advanced, aquesta es realitza en dos tipus d'escenaris diferents. D'una banda, els escenaris definits dins del procés d'avaluació de tecnologies IMT-Advanced. Dins d'aquest marc, s'avalua la importància de diferents tècniques de transmissió multi-antena, incloent-hi CoMP, i considerant tràfic de tipus full-buffer. S'ha obtingut una gran millora de prestacions amb la multiplexació espacial d'usuaris i una discreta millora amb CoMP. El segon grup d'escenaris són els definits pel projecte europeu METIS per a l'avaluació de tecnologies 5G, concretament s'han triat un escenari d'interiors amb una oficina, i un d'exteriors amb un estadi esportiu, on s'ha utilitzat un tràfic realista. En aquests escenaris amb desplegaments menys uniformes, o amb un nombre limitat de transmissors provocant la major part de la interferència, és on aquesta Tesi ha trobat la utilitat més gran de
Martín-Sacristán Gandía, D. (2016). 3GPP Long Term Evolution: Performance Analysis and Evolution towards 4G with Coordinated Multi-Point Transmission [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/63261
TESIS

Afin de satisfaire le besoin toujours croissant en débit et offrir toujours plus de services, ce où que les utilisateurs se trouvent, les réseaux cellulaires évoluent rapidement vers des technologies caractérisées par une interface radio de plus en plus sophistiquée. Par exemple, alors que le déploiement des réseaux 4G ne faisaient que commencer, les premières mises à jour vers les solutions LTE-A étaient déjà planifiées par les opérateurs, et actuellement, les technologies 5G font l'objet de recherches actives à travers le monde. Ces changements rapides sont motivés par l'explosion du trafic mobile, comme le montrent des nombreuses études et observations sur les réseaux actuels. Ce trafic est principalement généré par des utilisateurs équipés de smartphones, tablettes, et autres équipements mobiles. Cependant, les réseaux actuels ont du mal à s'adapter à cette proportion toujours grandissante d'utilisateurs mobiles et à leur fournir un service adapté. Dans ce contexte, un des enjeux importants pour les opérateurs et équipementiers est de disposer d'outils efficaces pour évaluer les performances de leurs réseaux et mieux les dimensionner. Cette thèse porte donc sur le développement de modèles analytiques, à la fois précis et simples d'utilisation, permettant de répondre aux problèmes posés par l'évaluation de performances dans les réseaux cellulaires de nouvelle génération. Les modèles s'appuient sur la théorie des files d'attente et des processus stochastiques et permettent d'évaluer les performances d'un réseau et de ses utilisateurs en tenant compte de leur mobilité. Dans un premier temps, sont présentés tour à tour des modèles dédiés aux différents types de cellules rencontrées dans les réseaux cellulaires et aux utilisateurs qui visitent ces cellules. Dans un second temps, des modèles dédiés à un réseau cellulaire dans son ensemble sont présentés. Ces modèles réseaux combinent les précédents modèles dédiés aux cellules et un modèle de routage reproduisant le routage des utilisateurs mobiles entre les différentes cellules qui constituent le réseau. Tous les modèles proposés ont été pensés afin d'obtenir des expressions simples de l'ensemble des paramètres de performances du système. Cette simplicité associée à la rapidité de résolution rend possible les études de performance des systèmes les plus complexes, comme en témoignent les nombreux exemples inclus dans cette thèse
In order to meet the ever-increasing need for bandwidth and to offer ever more services, wherever users are, cellular networks are rapidly evolving towards technologies characterized by an increasingly sophisticated radio interface. For example, while the deployment of 4G networks was just beginning, operators already planned the first updates to LTE-A solutions and 5G technologies are currently receiving active attention. These rapid changes are motivated by the explosion of mobile traffic, as shown by numerous studies and observations on current networks. Users equipped with smartphones, tablets, and other mobile devices mainly generate this traffic. However most of models for cellular networks in literature do not take into account mobility of users. Authors who have tried to take into account users' mobility, propose models based on hypotheses like users moving with infinite speed. In this thesis we have developed analytical models for 4G and 5G cellular networks taking into account user mobility in a realistic way. The proposed models were designed to be simple and easy to solve, allowing users and networks performance to be evaluated almost instantaneously. Our first analysis and results where on the impact of mobility in dense LTE-A networks with small cells. We developed two models to access static users performance in small cell with mixed users (static and mobile users). The first model is based on Markov chains and the second one on Processor-Sharing queue. Our second analysis and results where on LTE/LTE-A macrocells with two coding zones and visited by mobile users. We proposed a model based on queuing theory to study the performance of mobile users in a LTE/LTE-A macrocell with different radio conditions over its coverage area. Then, we have then extended these models to the case of homogeneous cellular networks where cells are statistically identical. These models allowed us to show the positive impact of user mobility on performance in a cell or in a network. Moreover, we showed that this performance gain was not a monotonous function of user mobility, which is an important result showing the impact of hard handover implemented in LTE and LTE-A networks on performance. Finally, we turned our attention to heterogeneous networks with different type of cells and visited by users with different profiles (speed, amount of data to be transferred)

Mobile networks are in the process of becoming the world’s leading medium for data traffic. This challenge has raised the bar for Quality of Services (QoS) provided by the mobile network operators. It requires methods and tools to verify the Service Level Agreement (SLA) and benchmark competitors by comparing metrics of QoS, e.g. the round-trip time and available bandwidth. For this purpose, Blixt™ has been developed, which is a property of InfoVista Sweden AB. Blixt™ is an Android application which measures the available bandwidth and the round-trip time for the latest generation of mobile networks. Blixt™ approach relies on a time-stamping protocol commonly known as Two-Way Active Measurement Protocol (TWAMP). This research work discusses how the packet probing parameters affect the accuracy of measurements and the level of intrusiveness. The performance of the technique was experimentally tested and compared to other tools and methods, namely, iPerf3, nPerf and FTP test.

The subject of the diploma thesis are procedures in EPS network related to the operation of mobile terminals. In the introduction of my work I described the EPS system, including the quality of services and bearers. The following section focuses on control procedures in the EPS system such as attach network procedure, detach procedure, service request, handover or tracking area procedure. Further, three technologies for Internet of Things were described, namely EC-GSM-IoT, LTE-M and NB-IoT. All the procedures mentioned above were also captured in the experimental VUT EPS network and analyzed by TravelHawk using software M5 and Wireshark. Theoretical and practical findings were subsequently used out for setting of laboratory task for subject MKPM.

碩士
國立成功大學
電腦與通信工程研究所
102
4G LTE is widespread in the world, recent years. Except having a higher transmitting speed than 3rd-generation(3G), also include more efficient resource allocation. However, there always exists an issue of power consumption of mobility equipment. Accordingly, we will introduce a technology called “Device-to-Device communication” undelaying LTE, which connect each equipment without Base Station (BS) and only need to make a link between two devices. Due to this way, the purpose of reducing power consumption can be realized. In the case of how much power should transmitter transmit, we will introduce an algorithm named “Alternating Direction Method of Multiplier”. We put these two methods jointly to find out the optimal solution of minimum power consumption.

碩士
國立中央大學
資訊管理學系在職專班
102
While telecom services in Taiwan move from the 3G services to 4G LTE high-speed access to the internet, both academics and practice pay a lot of attention on the operational strategy. According to foreign carriers operating mode, this study identified five factors: tariff design, innovative services, customer experience management, profit business models, bands building strategy. This study also integrated expert’s opinions for future development of Taiwan carriers 4G LTE service business model reference. This study found: 1.Service innovation: Instant billing and notification, instant promotions and purchase, guarantee access program. 2.Tariff plan innovation: a flexible data tariff plan, sharing internet downloads (sharing pool). 3.User experience innovation: User self-control and management usage. 4.Innovative profit model: user toll free web (Advertising) and OTT operators to launch unlimited data combinations promotions. 5.Proposal for strategies of the bands interoperability between telecom operators.

碩士
國立高雄應用科技大學
光電與通訊工程研究所
103
In this thesis, the study mainly focuses on the design of MIMO antennas for 4G LTE applications. The proposed antenna is based on outdoor, indoor and mobile device structure. According to each different case to be used different design ways. There are three types antenna design, and three kind of antennas size refer to commercial product in the chapters. The antenna design for 4G LTE band. In this thesis, the antenna designed with multi-input multi-output form as the mainly. The first advantage of this approach are increasing the radiation patterns and the effective range. The second advantage is increasing selectivity and provided more channel capacity. Eventually, system can choose the best antenna signal as the main source. At last, each antenna in envelope correlation coefficient have good performance and up to standards on the market.

碩士
國立臺北科技大學
電子工程系研究所
105
This paper describes a broadband microstrip leaky wave antenna for 4G LTE frequency bands : LTE 700 MHz、GSM 850 MHz、900 MHz、LTE 1500 MHz、1700 MHz、GSM 1800 MHz、1900 MHz、UMTS and LTE 2500 MHz、3500 MHz . The proposed antenna covers the frequency range from 0.7 GHz to 4 GHz for future frequency band expansion. The antenna design uses half-width microstrip structure to replace the traditional complex full width structure requiring differential excitation circuit. This proposed half width structure consists of long rectangular microstrip with short circuits formed by a series of metal via holes between the microstrip and the ground plane periodically. The measurement results show that maximum peak realized gain of 7 dBi is achieved. Measured return loss of antenna is larger than 6 dB in the operating bandwidth, and the low frequency band is relatively broad compared to the conventional microstrip leaky wave antenna.

碩士
國立臺南大學
綠色能源科技學系碩士班
102
For years personal wireless communication technology continues to development that people are becoming increasingly dependent on wireless communication, by the end of 2012 the global mobile users has reached 6.3 billion, and expected to 2018 the number will reach 7 billion. Meanwhile, the user of personal communication technology also has a new requirement: personal communication device miniaturization, low-power, high-frequency band and multimedia. Although 3G networks compared to 2G network the wireless performance has been greatly improved, but there still have a lot of limitations of market challenges and to meet user''s needs, and impact by Wi-Fi, the price is cheaper and the technology is not complicated. By all these needs, we need 4G technologies to bring us faster transfer, wider band and lower operating cost. To this end, this thesis proposes adapted to receive LTE 4G mobile broadband signal of printed antennas. Use CPW type as antenna''s design structure, the antenna length of 1/2 wavelength of design criteria. Two frequencies close to the modal broadband performance can be achieved, the antenna at the Return Loss ≦ -6 dB covered under the definition of LTE frequency band is 1790MHz to 2250MHz. It’s covering the LTE of the south America、the mainstream broadband of Asia area(2100MHz) and Eastern Europe(2300MHz). The antenna is designed on FR4 substrate, the final antenna dimensions is 50×50×0.8 mm3, the radiation patterns E-plane part of the traditional type monopole antenna 8-shaped patterns, and the H-plane part is omni-directional.

碩士
國立交通大學
電機資訊國際學程
103
依目前的趨勢來看，大約每10年就有新一代的行動通訊系統出現。而現今行動通訊技術集中於4G/LTE，並朝5G網路邁進。儘管5G規格尚未由電信標準化團體在任何公開的官方文件中描述，5G技術已超越了當前的4G/IMT-Advanced的標準，是下一個世代無線通訊技術的主要的標準。本論文旨在為4G/ LTE技術進行全面的調查，並介紹目前無線通訊技術之趨勢。除相關之技術介紹外，本論文還詳述交大寬頻移動實驗室（BML）四階段測試平台所開發之量測技術；為評估即時應用視訊流量的服務品質，亦進行了視訊流量在4G/LTE系統的量測，並針對封包遺失與擾動進行量測。本論文亦提出了現階段無線通訊技術的相關挑戰，以及將來轉移到下一代需要特別注意的技術。最後，總結本論文之研究，將用以評估越南的電信運營商，以期在越南電信市場上，以及目前部署的運營商，能夠作出合理的建議，以選擇適合的供應商。

碩士
國立臺北科技大學
電腦與通訊研究所
102
This paper presents a design of local oscillator, which is operated by User Equipment in a 4G LTE communication system operating Band 2(UL：1850 MHz - 1910 MHz). In order to design the local oscillator, the simulation tools of Advanced Design System, which was developed by Agilent Technologies Inc., was used to predict the characteristics of circuits. Meanwhile, The Clapp oscillator architecture(the combination of common emitter bipolar transistors and series resonant circuit), which was adopted by this paper, was based on voltage-controlled oscillator. About the fractional frequency synthesizer and combination with the third-order passive loop filter. In order to present a practical module of frequency synthesizer, the main chip of LMX2485E frequency synthesizer, the main circuit structure use the technology of delta-sigma modulator, which was developed by Texas Instruments Inc., was used to control the chip’s internal registers, different loop bandwidth’s loop filters and set the various parameters by the code loader. However, the LMX2485E frequency synthesizer module has some problem, therefore use the LMX2531 frequency synthesizer module which was developed by Texas Instruments Inc. to replace the original design of the circuit modules, and then fix the loop bandwidth to measure lock time, phase noise and other features., Finally, this paper analysis and discussion in 4G LTE communication system specification of the practical module’s performance measurement results.