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1
Carballo, Vega Edgar Raúl. "LTE Vs. Wimax móvil Vs. HSPA (HSUPA, HSDPA) como tecnologías de redes MAN". Thesis, Universidad de las Américas Puebla, 2013. http://catarina.udlap.mx/u_dl_a/tales/documentos/lem/carballo_v_er/.
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En este proyecto final se describe, se analiza y se compara la capa física de LTE (Long
Term Evolution) y WIMAX móvil (Worldwide Interoperability for Microwave Access), para
determinar la mejor tecnología en la implementación de una red de área metropolitana.
Se tienen dos estándares tecnológicos de dos grandes desarrolladores de tecnología de
telecomunicaciones.
Este proyecto final se concentra en la capa física de estos estándares, la cual se
encarga de asegurarse que la señal sea transportada exitosamente de un dispositivo a
otro. Se lleva a cabo la codificación, modulación y sincronización de señales.
El título del proyecto final, incluye HSPA (High Speed Packet Acces), con sus
propios estándares en su enlace de subida y su enlace de bajada, HSDPA (High Speed
Downlink Packet Acces) y HSUPA (High Speed Uplink Packet Acces) respectivamente
como tecnología de red de área metropolitana, la tecnología HSPA fue estandarizada
por 3GPP (3rd Generation Partnership Project), creada como complemento de WCDMA
(Wideband Code Division Multiple Access) para mejorar la velocidad de datos y así poder
obtener el máximo de beneficios en GSM (Global System for Mobile Communications)
para la tercera generación de telecomunicaciones. En la actualidad existe como
propuesta la nueva versión de HSPA llamada HSPA+ (evolución de HSPA), la cual
complementa a LTE para la transición de la red tercera generación a cuarta generación;
por lo que sólo se harámención de esta tecnología como trabajo futuro.
2
Bičík, Petr. "Vývoj a výhled mobilního připojení v ČR". Master's thesis, Vysoká škola ekonomická v Praze, 2008. http://www.nusl.cz/ntk/nusl-15376.
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Mobile telecommunications belong to one of the fields which still evolves and it is expected that in the future they are going to offer great benefit to the whole world. This work focuses on current and future development of mobile Internet connection in the Czech Republic. At first the technologies used to provide mobile Internet connection are described and compared and then the situation (in terms of technologies and mobile operators) in the Czech market is outlined and its possible evolution in the near future is presented. Furthermore, the tarifs of mobile operators are compared with those in place two years ago. The strengths and weaknesses of the current mobile Internet connection are evaluated based on the conducted questionnaire survey. The latest results are then analyzed and compared with the results from a previous survey conducted in 2007 as part of a bachelor's thesis, which has been further extended in this mater's thesis.
3
Liu, Tuo. "Analytical modeling of HSUPA-enabled UMTS networks for capacity planning". University of Sydney, 2009. http://hdl.handle.net/2123/4055.
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PhDIn recent years, mobile communication networks have experienced significant evolution. The 3G mobile communication system, UMTS, employs WCDMA as the air interface standard, which leads to quite different mobile network planning and dimensioning processes compared with 2G systems. The UMTS system capacity is limited by the received interference at NodeBs due to the unique features of WCDMA, which is denoted as `soft capacity'. Consequently, the key challenge in UMTS radio network planning has been shifted from channel allocation in the channelized 2G systems to blocking and outage probabilities computation under the `cell breathing' effects which are due to the relationship between network coverage and capacity. The interference characterization, especially for the other-cell interference, is one of the most important components in 3G mobile networks planning. This monograph firstly investigates the system behavior in the operation of UMTS uplink, and develops the analytic techniques to model interference and system load as fully-characterized random variables, which can be directly applicable to the performance modeling of such networks. When the analysis progresses from single-cell scenario to multi-cell scenario, as the target SIR oriented power control mechanism is employed for maximum capacity, more sophisticated system operation, `feedback behavior', has emerged, as the interference levels at different cells depend on each other. Such behaviors are also captured into the constructed interference model by iterative and approximation approaches. The models are then extended to cater for the features of the newly introduced HSUPA, which provides enhanced dedicated channels for the packet switched data services such that much higher bandwidth can be achieved for best-effort elastic traffic, which allows network operators to cope with the coexistence of both circuit-switched and packet-switched traffic and guarantee the QoS requirements. During the derivation, we consider various propagation models, traffic models, resource allocation schemes for many possible scenarios, each of which may lead to different analytical models. All the suggested models are validated with either Monte-Carlo simulations or discrete event simulations, where excellent matches between results are always achieved. Furthermore, this monograph studies the optimization-based resource allocation strategies in the UMTS uplink with integrated QoS/best-effort traffic. Optimization techniques, both linear-programming based and non-linear-programming based, are used to determine how much resource should be assigned to each enhanced uplink user in the multi-cell environment where each NodeB possesses full knowledge of the whole network. The system performance under such resource allocation schemes are analyzed and compared via Monte-Carlo simulations, which verifies that the proposed framework may serve as a good estimation and optimal reference to study how systems perform for network operators.
4
Smith, Brian J. "CELLULAR BROADBAND TELEMETRY OPTIONS FOR THE 21st CENTURY: Looking at broadband cellular from a telemetry perspective". International Foundation for Telemetering, 2006. http://hdl.handle.net/10150/604482.
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ITC/USA 2006 Conference Proceedings / The Forty-Second Annual International Telemetering Conference and Technical Exhibition / October 23-26, 2006 / Town and Country Resort & Convention Center, San Diego, CaliforniaWith the recent broadband upgrades to various cellular infrastructures and the myriad new emerging wireless broadband standards and services offered by carriers, it is often difficult to navigate this sea of technology. In deciding the best choice for broadband telemetry applications, one must look not only at the technology, but also at the economics, market timing, bandwidths, legacy issues, future expandability and coverage, security, protocols, and the requirements of the specific application. This paper reviews the technology roadmap of cellular providers keeping these issues in perspective as they apply to TCP/IP data for images, audio, video, and other broadband telemetry data using CDMA 1xRTT, EV-DO, and EV-DO Rev A systems as well as GSM GPRS/EDGE, UMTS/W-CDMA, HSDPA, and HSUPA networks. Lastly, issues seen by system integrators when using cellular channels for telemetry applications are examined, and a case is presented for overcoming many of these issues through the use of cellular routers.
5
Liu, Tuo. "Analytical modeling of HSUPA-enabled UMTS networks for capacity planning". Thesis, The University of Sydney, 2008. http://hdl.handle.net/2123/4055.
Pełny tekst źródłaStreszczenie:
In recent years, mobile communication networks have experienced significant evolution. The 3G mobile communication system, UMTS, employs WCDMA as the air interface standard, which leads to quite different mobile network planning and dimensioning processes compared with 2G systems. The UMTS system capacity is limited by the received interference at NodeBs due to the unique features of WCDMA, which is denoted as `soft capacity'. Consequently, the key challenge in UMTS radio network planning has been shifted from channel allocation in the channelized 2G systems to blocking and outage probabilities computation under the `cell breathing' effects which are due to the relationship between network coverage and capacity. The interference characterization, especially for the other-cell interference, is one of the most important components in 3G mobile networks planning. This monograph firstly investigates the system behavior in the operation of UMTS uplink, and develops the analytic techniques to model interference and system load as fully-characterized random variables, which can be directly applicable to the performance modeling of such networks. When the analysis progresses from single-cell scenario to multi-cell scenario, as the target SIR oriented power control mechanism is employed for maximum capacity, more sophisticated system operation, `feedback behavior', has emerged, as the interference levels at different cells depend on each other. Such behaviors are also captured into the constructed interference model by iterative and approximation approaches. The models are then extended to cater for the features of the newly introduced HSUPA, which provides enhanced dedicated channels for the packet switched data services such that much higher bandwidth can be achieved for best-effort elastic traffic, which allows network operators to cope with the coexistence of both circuit-switched and packet-switched traffic and guarantee the QoS requirements. During the derivation, we consider various propagation models, traffic models, resource allocation schemes for many possible scenarios, each of which may lead to different analytical models. All the suggested models are validated with either Monte-Carlo simulations or discrete event simulations, where excellent matches between results are always achieved. Furthermore, this monograph studies the optimization-based resource allocation strategies in the UMTS uplink with integrated QoS/best-effort traffic. Optimization techniques, both linear-programming based and non-linear-programming based, are used to determine how much resource should be assigned to each enhanced uplink user in the multi-cell environment where each NodeB possesses full knowledge of the whole network. The system performance under such resource allocation schemes are analyzed and compared via Monte-Carlo simulations, which verifies that the proposed framework may serve as a good estimation and optimal reference to study how systems perform for network operators.
6
Liu, Tuo. "Analytical modeling of HSUPA-enabled UMTS networks for capacity planning". Connect to full text, 2008. http://ses.library.usyd.edu.au/handle/2123/4055.
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Thesis (Ph. D.)--University of Sydney, 2009.Title from title screen (viewed February 20, 2009). Includes graphs and tables. Includes list of publications co-authored with others. Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Information Technologies, Faculty of Engineering and Information Technologies. Degree awarded 2009; thesis submitted 2008. Includes bibliographical references. Also available in print form.
7
Alinejad, Ali. "Cross layer ultrasound video streaming over mobile WiMAX and HSUPA networks". Thesis, Kingston University, 2012. http://eprints.kingston.ac.uk/23718/.
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It is well known that the evolution of 4G-based mobile multimedia network systems will contribute significantly to future m-health applications that require high bandwidth and fast data rates. Central to the success of such emerging applications is the compatibility of broadband networks such as mobile WiMAX (IEEE 802.16e) and RSVP A, and especially their rate adaption issues combined with the acceptable real time medical quality of service requirements. The design of effective broadband mobile healthcare systems usmg emerging WiMAX and RSxP A networks is important from the medical perspective especially in applications such as remote medical ultrasound diagnostic systems. In this thesis, we introduce a new cross layer design approach for medical video streaming over mobile WiMAX and RSVP A networks. In particular, we propose an approach based on optimising medical Quality of Service (m-QoS) in mobile WiMAX network environments described in this work. Preliminary performance analysis of the proposed cross layer algorithm has been evaluated via simulation studies. These results show that the proposed cross layer optimizer achieves improved performance compatible with the necessary medical QoS requirements and constraints for the relevant clinical application. Furthermore, this work addresses the relevant challenges of cross layer design requirements for real time rate adaptation of ultrasound video streaming in Mobile WiMAX and RSVP A networks. The comparative performance analysis of such approach is validated in two experimental m-health testbed systems for both Mobile WiMAX and RSVP A networks. The experimental results show an improved performance of Mobile WiMAX compared to the RSVP A using the same cross layer optimisation approach. Additionally, we map the medical QoS to typical WiMAX QoS parameters in order to optimise the performance of these parameters in typical m-health scenarios. Preliminary performance analysis of the proposed multiparametric scenarios is evaluated to provide essential information for future medical QoS requirements and constraints.
8
Jehličková, Lenka. "Základy mobilního internetu". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-218856.
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Thesis concerns with mobile communications theory with focus on data transfer. In the introduction the history, the origin and individual mobile systems generations are described. It is followed by detailed description of second, third and fourth generation mobile systems. Frequency band allocation, signal processing, the system architecture itself, security management and basic features are also discussed. The GSM system is described together with individual data transmission types based on circuit switching – CSD and HSCSD and packet switching – GPRS and EDGE. For UMTS, FDD and TDD modes are listed as well as changes in individual releases, corresponding technologies and provided services. Next, there is the description of LTE and WiMAX systems, together with their improvements whose are part of the fourth generation of mobile systems. Last of the described systems is the still work in progress HAPS, also known as the system of stratospheric platforms. In the end important parameters are summarized and systems are compared with each other.
9
Stenbom, Håkan. "Optimization of Remote ServiceSolution for large installations : Wireless LAN and WAN for ABB Robotics". Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-12083.
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This report describes a thesis work carried out at ABB Robotics in Västerås. The objective of this thesis is to find technologies and equipments for wireless data transfer suitable for the present and future needs of ABB Robotics Remote Service for large installations in industrial environments. ABB Robotics has a Remote Service solution to securely gather information from robots, manage alarms and potentially execute remote commands by ABB Robotics. This solution consists of an intelligent Service Box plugged to the robot. This Service Box is also connected through GPRS or directly through Internet to create a secure VPN connection to a central Remote Service server. The Remote Service Box is well suited for small customers with 1-10 robots with plug and play installation, but show limitations at a larger scale of deployment due to equipment costs, network and installation complexity. A new Service Box is planned that will accommodate future added functionality to Remote Service. This Service Box will require new network solutions as the added functionality is depending on a higher bandwidth than the GPRS networks can deliver. I have surveyed most existing wireless networking technologies and analyzed them withrespect to function, cost and availability which provide a knowledge base that makes it possible to find suitable solutions. When the most suitable technologies are identified a survey was performed to find equipments that meet the requirements at the lowest cost. A new hierarchical network topology is proposed that will lead to cost savings by replacing multiple WAN connections in the present solution with a network switch and single WAN connection to Internet. As manufacturers of network equipments for industrial environments are relatively few, alternative solutions were also investigated in order to find the most cost effective solutions. The proposed network topology together with the data from the surveys lead to recommendations on using Wi-Fi in the wireless LAN and a 3G mobile network for the WAN connection to Internet, as well as recommendations on alternative network equipments that potentially can lead to substantial savings when the new network solutions are implemented.
10
Saïdi, Taofik. "Architectures matérielles pour la technologie WCDMA étendue aux systèmes mulit-antennes". Phd thesis, Université Rennes 1, 2008. http://tel.archives-ouvertes.fr/tel-00446060.
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Depuis une dizaine d'années, l'avènement des techniques multi-antennes (ou MIMO) pour les communications sans fil, mobiles ou fixes, a révolutionné les possibilités offertes pour de nombreux domaines d'application des télécommunications. La disposition de plusieurs antennes de part et d'autre du lien augmente considérablement la capacité des systèmes sans fil. Cependant, les al- gorithmes numériques à mettre en œuvre pour réaliser ces systèmes sont autrement complexes et constituent un challenge quant à la définition d'architectures matérielles performantes. L'objectif du travail présent repose précisément sur la définition optimale de solutions architecturales, dans un contexte CDMA, pour contrer cette problématique. Le premier aspect de ce travail porte sur une étude approfondie des algorithmes spatio- temporels et des méthodes de conception en vue d'une implantation matérielle efficace. De nom- breux schémas de détection sont proposés dans la littérature et sont applicables suivant trois critères qui sont : la qualité de service, le débit binaire et la complexité algorithmique. Cette dernière constitue une contrainte forte pour une mise en application à faible coût de terminaux mobiles intégrant ces applications. Aussi, il est nécessaire de disposer d'outils performants pour simuler, évaluer et affiner (prototypage rapide) ces nouveaux systèmes, candidats probables pour les télécommunications de quatrième génération. Le second aspect concerne la réalisation d'un transcepteur multi-antennes sans codage de ca- nal, intégrant la technologie d'accès multiple par répartition de codes dans le cas d'un canal large bande. Un système mono-antenne WCDMA, généralisable à un nombre quelconque d'antennes, a été intégré et simulé au sein de la plate-forme de prototypage rapide Lyrtech. L'architecture développée intègre les principaux modules du traitement en bande de base, à savoir le filtrage de Nyquist, la détection des multiples trajets suivie de l'étape de détection. Le prototype MIMO- WCDMA développé est caractérisé par sa flexibilité suivant le nombre de voies entrantes, le for- mat d'entrée des échantillons, les caractéristiques du canal sans fil et la technologie ciblée (ASIC, FPGA). Le troisième aspect se veut plus prospectif en détaillant de nouveaux mécanismes pour réduire le coût matériel des systèmes multi-antennes. Le principe d'allocation adaptative de la virgule fixe est présenté dans le but d'adapter le codage des données suivant les caractéristiques du canal sans fil et de minimiser en conséquence la complexité du circuit. D'autre part, le concept d'ar- chitectures adaptatives est proposé afin de minimiser l'énergie consommée au sein d'un système embarqué suivant le contexte d'application.
11
Konuskan, Cagatay. "Turbo Equalization for HSPA". Thesis, Linköping University, Department of Electrical Engineering, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-54640.
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New high quality mobile telecommunication services are offered everyday and the demand for higher data rates is continuously increasing. To maximize the uplink throughput in HSPA when transmission is propagated through a dispersive channel causing self-interference, equalizers are used. One interesting solution, where the equalizer and decoder exchange information in an iterative way, for improving the equalizer performance is Turbo equalization.
In this thesis a literature survey has been performed on Turbo equalization methods and a chosen method has been implemented for the uplink HSPA standard to evaluate the performance in heavily dispersive channels. The selected algorithm has been adapted for multiple receiving antennas, oversampled processing and HARQ retransmissions. The results derived from the computer based link simulations show that the implemented algorithm provide a gain of approximately 0.5 dB when performing up to 7 Turbo equalization iterations. Gains up to 1 dB have been obtained by disabling power control, not using retransmission combining and utilizing a single receiver antenna. The algorithm has also been evaluated considering alternative dispersive channels, Log-MAP decoding, different code rates, number of Turbo equalization iterations and number of Turbo decoding iterations.
The simulation results do not motivate a real implementation of the chosen algorithm considering the increased computational complexity and small gain achieved in a full featured receiver system. Further studies are needed before concluding the HSPA uplink Turbo equalization approach.
12
Hameed, Farhan. "Rate Scheduling for HSDPA in UMTS". Thesis, Högskolan Dalarna, Datateknik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:du-3734.
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The introduction of a new technology High Speed Downlink Packet Access (HSDPA) in the Release 5 of the 3GPP specifications raises the question about its performance capabilities. HSDPA is a promising technology which gives theoretical rates up to 14.4 Mbits. The main objective of this thesis is to discuss the system level performance of HSDPAMainly the thesis exploration focuses on the Packet Scheduler because it is the central entity of the HSDPA design. Due to its function, the Packet Scheduler has a direct impact on the HSDPA system performance. Similarly, it also determines the end user performance, and more specifically the relative performance between the users in the cell.The thesis analyzes several Packet Scheduling algorithms that can optimize the trade-off between system capacity and end user performance for the traffic classes targeted in this thesis.The performance evaluation of the algorithms in the HSDPA system are carried out under computer aided simulations that are assessed under realistic conditions to predict the results as precise on the algorithms efficiency. The simulation of the HSDPA system and the algorithms are coded in C/C++ language
13
Iqbal, Javed, i Basit Mustafa. "Scheduling Algorithms and QoS in HSDPA". Thesis, Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-1181.
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High Speed Downlink Packet Access (HSDPA) is the extension to the Universal Mobile Telecommunication System (UMTS). HSDPA allows for higher data rates due to new adaptive Modulation and Coding (AMC) techniques, Hybrid Automatic Repeat reQuest (H-ARQ) and fast scheduling algorithm. One of the key features of HSDPA technology is to handle UMTS traffic classes with different Quality of Service (QoS) requirements. In order to provide QoS several scheduling algorithms, QoS control constraints, and different other schemes have been proposed in literature. In the thesis, a simple matlab based model for HSDPA is presented in order to simulate various algorithms. The QoS controls in terms of guaranteed bit rate (GBR) have been implemented by means of barrier functions which perform barrier around the feasible region. The results illustrate the trade-off between the cell throughput and the minimum guaranteed bit rate. Traffic classes are prioritized by means of QoS parameters. The priority is given to RT traffic streams over interactive services. Real-Time (RT) algorithms have been simulated to prioritize traffic classes based on delays.QoS is the ability to provide resources and prioritize different applications. As mentioned before, the 3GPP standard defines four categories of service (Conversation, streaming, interactive and background) for UMTS. Strategies in traffic management, priority GBR allowances and bandwidth are important strategies for traffic differentiation and quality of service (QoS). Providing QoS over HSDPA is one of the challenging tasks for researchers. The significant results and findings of our thesis are as follows • In this thesis various algorithms were implemented with their duties barrier to provide guarantees of quality, in terms of speed guaranteed (GBR). The emphasis was to ensure the flow and priority categories of traffic. First the performance of algorithms were studied alone and then along with the barrier functions. It is concluded that barrier functions play an important role by means of providing QoS guarantee in HSDPA, considering channel conditions. Traffic classes were prioritized on QoS parameters defined for barrier functions. It was found that minimum bit rates were maintained by barrier functions but the cell throughput decreases with their barrier functions depending upon QoS parameters. The streaming aware scheduler has been evaluated by means of simulations in mixed scenarios and it is concluded that this algorithm protects streaming QoS in high overload conditions. It is therefore concluded that barrier functions and streaming aware schedulers are the best option for QoS control. These schedulers are very simple and consider diversity gains as well.
14
Szabo, Andrei. "Evaluation of MIMO concepts in HSDPA by system level simulations". Aachen Shaker, 2008. http://d-nb.info/992012600/04.
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Assaad, Mohamad. "Etude Multi-couches dans le système HSDPA". Phd thesis, Télécom ParisTech, 2006. http://pastel.archives-ouvertes.fr/pastel-00001877.
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L'augmentation de l'utilisation de l'Internet et des services de données motive l'évolution des réseaux cellulaires de troisième. Dans ce contexte, HSDPA (High Speed Downlink Packet Access) a été développé dans les releases 5 et 6 au sein de 3GPP pour poursuivre l'évolution du mode "paquet" de l'UMTS. Ce système utilise de nouvelles technologies telles que le Hybrid-ARQ (Automatic Repeat Request), la modulation adaptative et l'ordonnancement rapide (fast Scheduling) pour permettre de véhiculer des débits plus élevés sur l'interface radio et d'augmenter la capacité. Cette thèse se focalise sur l'analyse et la modélisation des interactions entre la couche MAC-hs de HSDPA et les autres couches (physique, transport). L'objectif est de trouver la configuration optimale de cette entité MAC-hs afin de réduire les interactions "négatives" entre-couches et optimiser les performances de HSDPA. Par conséquent, cette thèse fournit des études et des modélisations analytiques couvrant les aspects suivants: -Analyse et modélisation de l'impact du canal radio (shadowing, fast fading) sur les performances du système HSDPA dans le cas où plusieurs "schedulers" sont utilisés -Analyse et modélisation de l'effect des services "Circuit" de l'UMTS R99 sur les performances de HSDPA. -Modélisation de l'interaction entre le protocole TCP et l'entité MAC-hs. Une nouvelle stratégie d'ordonnancement est proposée afin d'améliorer les performances du système -Charactérisation de l'interaction entre MAc-hs et les services streaming. Une nouveau "scheduler" est proposé afin de garantir les contraintes sévères de QoS des services streaming sans trop perdre de capacité cellulaire.
16
Wang, Xiaoxin. "3G HSDPA Performance In Mobile Internet Connections". Thesis, KTH, Mikroelektronik och Informationsteknik, IMIT, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-93068.
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A key objective for 3G wireless networks, such as the Universal Mobile Telecommunication System (UMTS), is the explicit support for data communications for mobile users. Today, the dominant transport protocol in the Internet is the Transport Control Protocol (TCP). Since TCP was not tailored for wireless networks, there are some performance issues occurring when TCP traffic is transferred over a UMTS radio link. In this paper, the characteristics of TCP and UMTS are specified and the problems of TCP over UMTS dedicated channels (DCHs) are analyzed. The problem is high delays implying low utilization of allocated resources for small file transfers or due to packet losses. High Speed Downlink Packet Access (HSDPA)’s potential to solve the problem is studied. Since in HSDPA, High-Speed Downlink shared channel (HS-DSCH) is introduced as an alternative of DCH on downlink packet access, a model of HS-DSCH is built and simulations are performed in order to compare its TCP performance with DCH. The focus is on studying retransmission delay and Block Error Rate (BLER) targets. Some scheduling methods are also compared. The results indicate that HS-DSCH gives better TCP performance than a DCH, and that advanced scheduling methods gives similar result as round robin if there are packet losses. Moreover, a somewhat surprising result is found regarding fast retransmission and channel utilization for increasing BLER targets.I denna rapport specificeras karaktäristiken för TCP and UMTS, och problemet med TCP över dedikerade UMTS kanaler analyseras. Problemet är höga fördröjningar som medför låg utnyttjande grad av allokerade resurser vid överföring av små filer eller vid paket förluster. High Speed Downlink Packet Access (HSDPA)’s potential att lösa problemet studeras. En modell av HS-DSCH konstrueras och simuleringar utförs för att jämföra dess TCP prestanda med DCH. Fokus är på att studera återsändningsfördröjning och BLER riktvärden. Några scheduleringsmetoder jämförs också. Resultatet indikerar att HS-DSCH ger bättre TCP prestanda än DCH, och att avancerad scheduleringsmetoder ger liknande resultat som round robin vid paket förluster. Dessutom har ett ganska överraskande resultat funnits kring snabb återsändning och kanal utnyttjande grad då BLER riktvärdet ökar.
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Shen, Hui. "Regulation der Transkription des hspA-Gens in Stigmatella aurantiaca und Analyse der Funktion des HspA-Proteins". [S.l. : s.n.], 1999. http://deposit.ddb.de/cgi-bin/dokserv?idn=961946296.
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Husain, I. "Studies on the mitochondrial Hsup(+)-ATPase complex and its interaction with the Hsup(+)-ATPase inhibitor protein". Thesis, University of Leeds, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355705.
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Siraj, Fahd Muhammad. "HTTP Based Adaptive Streaming over HSPA". Thesis, KTH, Kommunikationsnät, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-53517.
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MPEG has developed various technologies for multimedia storage and delivery, such as MPEG-2 TS and MP4 file format. HTTP-based Adaptive Streaming is a new technology to deliver such multimedia streams over the Open Internet to a variety of consumer devices including set-top boxes, hybrid TVs, PC and portable devices. The examples include Apple HTTP Live Streaming, Microsoft SmoothStreaming, 3GPP Adaptive HTTP Streaming and the recent MPEG standardization activity related to Dynamic Adaptive Streaming over HTTP (DASH). The optimization tools used within these techniques try to cope with the underlying network conditions such as the bit rate variations and delay, along with user interaction. In this work I intend to setup and evaluate the performance of HTTP-based Adaptive Streaming Technologies over an HSPA network.
20
Melo, Emilio Honorio de. "Análise de tráfego de redes 3G/HSPA". Universidade Federal de Pernambuco, 2010. https://repositorio.ufpe.br/handle/123456789/2399.
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Previous issue date: 2010Nos últimos anos, as operadoras de telefonia móvel estão investindo na implantação e expansão de suas redes de terceira geração 3G/HSPA. O volume de tráfego de dados dessas redes crescem a taxas elevadas, o que demanda altos investimentos e celeridade no incremento por mais capacidade, exigindo das operadoras a racionalização de seus recursos, para garantir um grau de serviço adequado aos seus clientes e o aprimoramento no conhecimento dessas redes. Atualmente, este processo de racionalização é norteado por métricas tradicionais geradas pelos sistemas de gerenciamento e monitoramento de rede das operadoras (Operation SubSystem - OSS). Porém, o conhecimento da composição do tráfego de dados na rede 3G pode oferecer maiores detalhes e informações complementares para ações de dimensionamento e aferições da rede e o planejamento de políticas para os seus usuários de uma maneira mais precisa. No entanto, o potencial das informações extraídas de amostras de tráfego de pacotes na rede 3G ainda não foi devidamente investigado. Este trabalho objetiva realizar uma análise do comportamento de tais redes, através de coleta de dados numa interface IuPS e também de medições disponíveis no OSS de uma operadora móvel comercial brasileira. A partir dessa análise, fornecemos meios de se conhecer o perfil de seus usuários e um conjunto de métricas que proporcionem um melhor entendimento de seu funcionamento. Tais métricas assumem um papel de destaque nas tomadas de decisões gerenciais nas áreas técnica e comercial
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Freudenthaler, Klemens. "Investigation of the HSDPA system and its MIMO extension /". Linz : Trauner, 2008. http://opac.nebis.ch/cgi-bin/showAbstract.pl?u20=9783854994169.
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Zhao, Haichuan Jianqiu Wu. "Implementation and simulation of HSDPA functionality with ns-2". Thesis, Linköping University, Department of Electrical Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2833.
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Enhanced packet-data access is a trend in third generation mobile communication system. WCDMA Release 5 introduces HSDPA (High Speed Packet Data Access) with a brand new downlink transport channel HS-DSCH (High Speed Downlink Shared Channel) into 3GPP specification to provide greater capacity. HS-DSCH supports some new feature such as fast link adaptation, fast scheduling and fast HARQ (hybrid ARQ) so as to increase system performance. It efficiently improves power utilization, shortens retransmission time and increases system throughput.
The focus for this thesis is implementation and simulation of HSDPA functionality with ns-2. There is some previous work has been done, such as EURANE. EURANE is an end to end extension which adds several HSDPA modules to ns-2. This paper addresses the analysis of HSDPA by simulating on HS-DSCH based on EURANE, and extends the power consumption on HS-DSCH.
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Braga, Andrà Ribeiro. "Controle de congestionamento para voz sobre IP em HSDPA". Universidade Federal do CearÃ, 2006. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=2073.
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nÃo hÃO crescimento do nÃmero dos usuÃrios do serviÃo de Voice over IP(VoIP) faz dele o serviÃo com o maior interesse de ser provido por operadoras de telefonia celular. Por outro lado, este demanda um controle de Quality of Service (QoS) bastante rÃgido, o que torna-se mais complicado em redes sem fio, porque alÃm de congestionamentos na rede, os pacotes podem ser perdidos devido à erros nas transmissÃes no enlace de rÃdio. Dentro deste paradigma, estratÃgias de controle de congestionamento aparecem como uma boa soluÃÃo para lidar com as garantias de QoS em situaÃÃes de sobrecarga do sistema, onde os recursos se encontram exauridos e os requerimentos de qualidade se encontram ameaÃados. Este trabalho consiste na avaliaÃÃo de algoritmos de controle de congestionamento objetivando um aumento de capacidade e das garantias de QoS para serviÃos de voz. Os algoritmos avaliados neste trabalho sÃo os escalonamentos de pacotes e os controles de admissÃo. A anÃlise em cenÃrios de serviÃos mistos composto por usuÃrios VoIP e Web tambÃm està contida neste trabalho. O maior foco està no controle do atraso de pacote, jà que este à um requerimento crucial para serviÃos de tempo-real, como o VoIP. Os resultados mostram que um arcabouÃo de controle de congestionamento projetado para este serviÃo à capaz de melhorar o desempenho do sistema e mitigar os efeitos de congestionamento da rede. No cenÃrio de serviÃos mistos, os algoritmos sÃo capazes de efetuar reserva de recursos dependendo da prioridade definida para cada serviÃo, levando a um aumento na qualidade percebida pelo serviÃo mais sensÃvel atravÃs de uma leve degradaÃÃo no serviÃo mais robusto.
The growth in the number of Voice over IP(VoIP) users on the internet makes it the service with the highest interest to be provided by cellular operators. On the other hand, it demands very strict Quality of Service (QoS) control, which becomes even more complicated in wireless networks, because packets can be lost due to radio link transmission erros, as well as networks congestion. Within this paradigm, congestion control strategies appear as a good solution to cope with QoS guarantees under high loads, where the resources are exhausted and the service quality is threatened. This works comprises the evaluation of congestion control algorithms aiming to improve system capacity and QoS guarantees for speech users. The evaluated alagorithms within this work are packet scheduling and admission control. The analysys in mixed services scenarios composed of VoIP and Web users is also provid in this works. The main focus of the framework is to control the packet delay, since it is a crucial requirement for real-time services. The results show thata suitable congestion control framework is able to provid perfomace improvements and mitigation of the the effects from overloaded conditions. In the mixed services scenario, the algorithms are capable to perform resource reservation depending on the priority defined to each service, leanding to an increase in the quality of more sensitive service by degrading the more robust service
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Braga, André Ribeiro. "Controle de congestionamento para voz sobre IP em HSDPA". reponame:Repositório Institucional da UFC, 2006. http://www.repositorio.ufc.br/handle/riufc/15983.
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BRAGA, A. R. Controle de congestionamento para voz sobre IP em HSDPA. 2006. 98 f. Dissertação (Mestrado em Engenharia de Teleinformática) – Centro de Tecnologia, Universidade Federal do Ceará, Fortaleza, 2006.Submitted by Marlene Sousa (mmarlene@ufc.br) on 2016-04-01T17:58:37Z No. of bitstreams: 1 2006_dis_arbraga.pdf: 974057 bytes, checksum: 283818878c8d44ed883fa749a672d3d7 (MD5)
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The growth in the number of Voice over IP(VoIP) users on the internet makes it the service with the highest interest to be provided by cellular operators. On the other hand, it demands very strict Quality of Service (QoS) control, which becomes even more complicated in wireless networks, because packets can be lost due to radio link transmission erros, as well as networks congestion. Within this paradigm, congestion control strategies appear as a good solution to cope with QoS guarantees under high loads, where the resources are exhausted and the service quality is threatened. This works comprises the evaluation of congestion control algorithms aiming to improve system capacity and QoS guarantees for speech users. The evaluated alagorithms within this work are packet scheduling and admission control. The analysys in mixed services scenarios composed of VoIP and Web users is also provid in this works. The main focus of the framework is to control the packet delay, since it is a crucial requirement for real-time services. The results show thata suitable congestion control framework is able to provid perfomace improvements and mitigation of the the effects from overloaded conditions. In the mixed services scenario, the algorithms are capable to perform resource reservation depending on the priority defined to each service, leanding to an increase in the quality of more sensitive service by degrading the more robust service
O crescimento do número dos usuários do serviço de Voice over IP(VoIP) faz dele o serviço com o maior interesse de ser provido por operadoras de telefonia celular. Por outro lado, este demanda um controle de Quality of Service (QoS) bastante rígido, o que torna-se mais complicado em redes sem fio, porque além de congestionamentos na rede, os pacotes podem ser perdidos devido à erros nas transmissões no enlace de rádio. Dentro deste paradigma, estratégias de controle de congestionamento aparecem como uma boa solução para lidar com as garantias de QoS em situações de sobrecarga do sistema, onde os recursos se encontram exauridos e os requerimentos de qualidade se encontram ameaçados. Este trabalho consiste na avaliação de algoritmos de controle de congestionamento objetivando um aumento de capacidade e das garantias de QoS para serviços de voz. Os algoritmos avaliados neste trabalho são os escalonamentos de pacotes e os controles de admissão. A análise em cenários de serviços mistos composto por usuários VoIP e Web também está contida neste trabalho. O maior foco está no controle do atraso de pacote, já que este é um requerimento crucial para serviços de tempo-real, como o VoIP. Os resultados mostram que um arcabouço de controle de congestionamento projetado para este serviço é capaz de melhorar o desempenho do sistema e mitigar os efeitos de congestionamento da rede. No cenário de serviços mistos, os algoritmos são capazes de efetuar reserva de recursos dependendo da prioridade definida para cada serviço, levando a um aumento na qualidade percebida pelo serviço mais sensível através de uma leve degradação no serviço mais robusto.
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Ba, Ahmet. "Développement de récepteurs avancés pour les systèmes de communication mobile de type WCDMA et HSDPA". Phd thesis, Télécom ParisTech, 2006. http://pastel.archives-ouvertes.fr/pastel-00001766.
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Dans la première partie de la thèse, on considère des méthodes d'estimation des canaux utilisateurs dédiés en liaison descendante. Ces méthodes sont particulièrement avantageuses dans un contexte de transmission à formation de faisceaux. Elles ne supposent aucune connaissance a priori des retards des signaux reçus ainsi que les paramètres de formation des faisceaux; exploitent la totalité des séquences pilotes transmises ainsi que la dynamique structurée du canal.Dans la seconde partie, on commence par considérer un schéma d'égalisation au niveau chip et dite HDD-NLMS. Ce schéma utilise l'estimation de la précédente séquence chip comme réponse cible pour l'adaptation de l'égaliseur. Dans la suite propose les égalisateurs niveau symbole HSDPA N-Griffith et HDD-NLMS qui permettent une vitesse d'adaptation 16 fois plus élevée que dans le cas de l'utilisation des symboles PCPICH. Les solutions spécifiques HSDPA ont une complexité raisonnable et offrent des performances proches aux Max-SINR dans un environnement réel.Dans la dernière partie, nous évaluons l'avantage des égalisateurs au niveau chip par rapport au récepteur Rake conventionnel ainsi que l'avantage d'une décision hard par rapport à l'utilisation d'une contre réaction linéaire dans le contexte d'un récepteur avec élimination itérative parallèle des interférences. Cette contre réaction sera déduite d'un développement polynomial de l'inverse de la matrice de covariance en amont du premier étage d'égalisation. Etant donné que les égalisateurs à chaque étage sont différents, nous utilisons les résultats d'analyse des étages précédents afin de pouvoir estimer les paramètres de l'égalisateur à un étage donné.
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Revilla, Apac Odalys Juliette. "Diseño de una red HSDPA en la ciudad de Huancayo". Bachelor's thesis, Pontificia Universidad Católica del Perú, 2011. http://tesis.pucp.edu.pe/repositorio/handle/123456789/838.
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La presente tesis consiste en el diseño de una red HSDPA para la ciudad de Huancayo.
El primer capítulo está centrado el la problemática que se presenta en Huancayo con respecto al servicio 3G y sobre el análisis de los objetivos a los que se quiere llegar
con las posibles soluciones.
El segundo capítulo abarca el marco teórico, donde se estudió sobre la evolución de
las tecnologías móviles y posteriormente se centró en la tecnología HSDPA para estudiar su arquitectura y demás parámetros de esta tecnología.
En el tercer capítulo se presenta un análisis socio-económico de la ciudad de Huancayo, donde se estudia a su población económicamente activa y como esta se va
desarrollando conforme a las a nuevas tecnologías móviles, con la finalidad de poder
determinar un posible mercado potencial.
El cuarto capítulo trata sobre la parte de ingeniería de la red; es decir, los cálculos de
cobertura de la red para poder determinar los nodos B, cálculos de capacidad de cada
Nodo B, los cálculos de la red de transporte y, por último, los equipos a usar para la
implementación.
El quinto capítulo está enfocado en la parte económica del proyecto, donde se
analizará la inversión del proyecto, los costos de operación y mantenimiento de la red, los ingresos por abonados; para finalmente determinar si el proyecto es rentable o no.Tesis
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Goffard, Molina Pablo Felipe. "Descarga de datos a alta velocidad con hsdpa sobre umts". Tesis, Universidad de Chile, 2007. http://www.repositorio.uchile.cl/handle/2250/104729.
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Barrow, John H. "Revising the BGSU Mathematics Placement System". Bowling Green State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1245699733.
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Schämann, Marcus. "Entwurf von digitalen Basisband-Komponenten eines HSDPA-Empfängers auf System-, Algorithmen- und Architekturebene mit Minimierung der Verlustleistung". Tönning Lübeck Marburg Der Andere Verl, 2008. http://d-nb.info/989527743/04.
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Martelli, Chiara. "Multi-standard low-power base-band digital receiver, enhanced for HSDPA /". Konstanz : Hartung-Gorre, 2006. http://www.loc.gov/catdir/toc/fy0707/2007366221.html.
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Originally presented as the author's thesis (Swiss Federal Institute of Technology), Diss. ETH No. 16683.Summary in Italian and English; text in English. Includes bibliographical references (p. 171-177).
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Chungtragarn, Anusorn. "MIMO-HSDPA : an approach to enhance the performance of wireless networks". Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/24430.
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The thesis focuses on improving the performance of wireless networks including energy efficiency and the maximum capacity of the network. In wireless networks such as ad hoc networks, they have been observed that the physical transmission rate is a vital parameter. For slow data rate networks, not only the end-to-end throughput is poor, the energy efficiency is also not good, because the transmission energy cannot be consumed effectively. In order to improve both performance matrices, this thesis proposes the use of MIMO-HSDPA techniques collaborating with an optimal resource allocation technique. When using the MIMO-HSDPA approach, it will be demonstrated in the thesis that the total physical data rate increases significantly, which render the improvement in both energy efficiency and the end-to-end throughput. In chapter 2, the performance of stationary ad hoc networks has been examined. The network uses the HSDPA technique to improve the physical data rate whilst a multipath routing communication with the load balancing algorithm is also employed to maximize energy efficiency. The focus of the chapter is on optimizing a packet size in order to achieve the target end-to-end throughput required by a user. The packet length optimization involves the analysis and modification of the MAC service time model, which will be used to determine the optimum packet size. In chapter 3, for further improvement of the physical data rate, the MIMO transmission technique is employed in collaboration with the HSDPA approach. However, when increasing the data rate, fading in the communication channel fluctuates and has effects on the received signal. The fading causes the communication channel to be a frequency selective channel, which renders an Inter-Symbol-Interference (ISI) in the received signal and the subsequent reducing in the performance of the receiver. The chapter shows how to allocate energy in the MIMO-HSDPA communication system where a channel is considered as a frequency selective channel. In order to mitigate the effect of the ISI the successive interference cancellation (SIC) technique is also used at the receiver. By using the energy allocation and the SIC technique, the maximum capacity of the system is greatly enhanced and is close to the upper bound capacity achieved by the water-filling algorithm. The communication channels being examined in the thesis mainly are type of pedestrian A channels. The channels are assumed to represent Wireless LAN systems, which are used only for short distance communications. Once MIMO techniques are applied, antenna configurations might produce spatial correlations on the pedestrian A channels, which causes reduction in the capacity given by a spatial multiplexing gain of the MIMO systems. In chapter 4 chapter, the capacity of the MIMO-HSDPA systems over correlated channels is identified and, in order to improve the performance, MIMO pre-coding techniques such as an Eigen value and a channel inverse pre-coding approach are proposed to deal with the correlated channel problem.
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Ma, Irina Chi Wai. "Transceiver optimisation for MIMO high-speed downlink packet access (HSDPA) system". Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/23285.
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In recent years, the growth of smart phone industry drives its users to demand better quality multimedia services while achieving faster internet speeds. With a higher number of subscribers and more data hungry applications, there is a need to improve the current 3G HSDPA data rate until the 4G network is fully implemented globally. Therefore, the aim of this thesis is to improve the downlink data rate of the HSDPA system throughput through both transmitter and receiver optimisations while balancing the complexities of the optimisation algorithms. Initially, improving system throughput through power allocation strategies is investigated in this thesis. Current schemes proposed in the literature that use Equal SINR Equal Rate (ESER) allocation can improve the system throughput for single rate allocation but require a rather high complexity. In this thesis, a System Value (SV) criterion is proposed to decrease the traditional ESER allocation method while achieving similar system throughput performance. To further increase the system throughput, a Successive Interference Cancellation (SIC) receiver is proposed which not only improves the data rate but also has a reduced complexity. The proposed SIC receiver can be used in conjunction with both ESER allocation schemes as well as equal energy allocation schemes. Another transmitter optimisation strategy is to improve the signature sequences. A signature sequence design that minimises correlations between the sequences while reducing the Inter-Symbol Interference (ISI) and noise is proposed. To reduce the amount of channel state information required, a signature sequence selection method which removes the signature sequences that are heavily affected by interference is also proposed. The proposed optimisation strategies have been verified through MATLAB simulations. Moreover, practical measurements using the National Instruments (NI)-PXIe testbed have been carried out for the proposed SIC algorithm which further confirm its effectiveness in a real world environment.
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Cardoso, Fabbryccio Akkazzha Chaves Machado. "Aplicações de antenas inteligentes e equalização concorrente em sistemas WCDMA/HSDPA". [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/261738.
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Orientador: Dalton Soares ArantesDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
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Resumo: Nesta tese são investigados e propostos diferentes algoritmos adaptativos para antenas inteligentes e equalização em receptores de usuário no enlace de descida de sistemas WCDMA/HSDPA. Considerando o tema de equalização de canal, propõe-se um algoritmo adaptativo de retro-propagação com subsistemas concorrentes. Esta técnica de equalização explora características específicas de um sinal WCDMA e foi inspirada na técnica de equalização cega concorrente desenvolvida por Fernando C. C. de Castro et al. Com relação a antenas inteligentes, propõe-se um esquema adaptativo de recepção espaço-temporal de múltiplos alvos, denominado MT-STR, que emprega K processadores de antenas e um com binador de sinais dos vários alvos, ou fingers, do receptor. Esta técnica de recepção foi testada num cenário de soft-handover bastante severo, envolvendo muitos sinais interferentes. Ainda no escopo de antenas inteligentes, estudou-se também o efeito do acoplamento mútuo e do descasamento de amplitude e fase em arranjos co-lineares de antenas dipolo de meia onda
Abstract: This dissertation investigates and proposes different algorithms for smart antennas and channel equalization aiming at WCDMA HSDPA downlink receivers. Considering the channel equalization issue, we propose an adaptive back-propagation algorithm with concurrent sub-systems. This equalization technique exploits particular characteristics of a WCDMA downlink signal and is based on the concurrent blind equalization technique developed by Fernando C. C. de Castro et al. For smart antennas, a multi-target space-time receiver (MT-STR) which uses K array processors and an adaptive ratio combiner is proposed. This technique has been tested under a severe soft-handover scenario assuming many interferers. The effects of mutual coupling and amplitude phase mismatch on co-linear half-wave dipole arrays for WCDMA down1ink receivers are also investigated.
Mestrado
Telecomunicações e Telemática
Doutor em Engenharia Elétrica
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Sousa, Leonardo Ramon Nunes de. "AvaliaÃÃo da Qualidade de Voz do ServiÃo VoIP em Sistemas HSDPA". Universidade Federal do CearÃ, 2007. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=2015.
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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgicoNos Ãltimos anos, observa-se o surgimento e a rÃpida disseminaÃÃo do serviÃo VoIP, integrando-se ao mercado atual junto à telefonia convencional e Ãs redes celulares. Por ser uma alternativa tecnolÃgica que contribui para minimizar ustos, assiste-se a uma preferÃncia crescente por fazer fegar a voz atravÃs das redes IP. O HSDPA, como sistema celular, permite a transmissÃo de dados em alta velocidade, aumenta a largura de banda da rede e abre novas possibilidades de serviÃos multimÃdia, como o VoIP que utiliza a transmissÃo em banda larga para telefones mÃveis. Exige-se, porÃm, um considerÃvel esforÃo de anÃlise deste serviÃo, pois o atraso inerente a esse sistema à um desafio para a garantia de qualidade de voz. Estes fatos justificam, conseqÃentemente, um esforÃo de anÃlise que se detenha sobre a qualidade de voz no VoIP sobre o HSDPA. Para avaliar a qualidade de voz, neste estudo aplica-se o mÃtodo MOS, que faz corresponder valores numÃricos a categorias como medidas de qualidade e inteligibilidade da voz transmitida, obtendo-se esses dados de forma objetiva e subjetiva. O processo de avaliaÃÃo dividiu-se em etapas de acordo com cada metodologia, seguindo recomendaÃÃes tÃcnicas e atravÃs de simulaÃÃes computacionais dinÃmicas. Na avaliaÃÃo objetiva, utilizou-se o algoritmo PESQ para obtenÃÃo do conceito MOS, enquanto que na avaliaÃÃo subjetiva, arquivos de voz com certo percentual de erro foram colocados em um endereÃo na Internet para escuta e atribuiÃÃo de nota MOS, baseada na percepÃÃo do usuÃrio ouvinte. Os resultados mostraram que os dois mÃtodos de avaliaÃÃo obtiveram conceitos de qualidade satisfatÃrios, que o QoS nas simulaÃÃes à estÃvel e positivo, que uma boa qualidade para os arquivos de voz e a provÃvel satisfaÃÃo dos usuÃrios do serviÃo VoIP sobre o sistema celular HSDPA à garantida para uma taxa de 2% de FER. Finalmente, mostra-se que a metodologia objetiva garante a obtenÃÃo de notas MOS aproximadas da subjetiva, evitando o Ãrduo trabalho de fazerem-se ouvir diversos arquivos de voz por uma quantidade significativa de usuÃrios para ser vÃlida estatisticamente.
In recent years, we can observe the development and fast dissemination of VoIP services, being integrated by the present market, beside conventional telephony and cellular networks. For being a technological alternative that contributes to minimize costs, we see an increasing preference for voice transmission through IP networks. HSDPA, as a cellular system, allows high speed data transmission,increases the network width of band and creates new possibilities for multimedia services, as VoIP that transmits in wideband to mobile telephones. The delay inherent to this system, however, is a challenge for the need to assure good quality of voice transmissions, demanding a considerable effort of analysis of this service.These facts justify a study that focus on the quality of voice in VoIP over HSDPA.To evaluate the voice quality, in this study, we applied MOS method that makes numerical values correspond to categories like quality and intelligibility of transmitted voice, getting these data through objective and subjective methodologies. The evaluation process was divided in fases according to the characteristics of each methodology and to technical recommendations, and was done through dynamic computational simulations. For objective evaluation process,algorithm PESQ was employed to obtain MOS concepts, whereas, for subjective evaluation, voice files with a percentage of error have been placed in Internet for listening and for the attribution of MOS concepts based in the perception of the listener. The results of this research show that both evaluation methods got satisfactory concepts of quality, that QoS is steady and positive in the simulations, that a good quality for the voice files and the probable satisfaction of the users of the VoIP service on cellular system HSDPA is guaranteed for 2% FER rate. Finally, it shows that MOS concepts produced by objective methodology were close enough to those given by subjective evaluation to dispense with the arduous work of making diverse voice files to be heard and subjectively evaluated by a statisticaly valid amount of users.
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Et-Tolba, Mohamed. "Transmission de données pour le HSDPA et étude des algorithmes HARQ". Télécom Bretagne, 2007. http://www.theses.fr/2006TELB0024.
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L’évolution majeur de l’UMTS, ces dernières années est le HSDPA (High Speed Downlink Packet Access) qui est basé sur la transmission en mode paquet. Il est conçu pour répondre au besoin en débit des utilisateurs dans la liaison descendante. Le HSDPA permet d’atteindre des débits qui peuvent dépasser 10 Mbits/s. Ceci est possible grâce à l’utilisation du principe de transmission multicodes en application conjointe avec de nouvelles technologies telles que la modulation et codage adaptatifs (MCA) ainsi que l’HARQ (Hybrid Automatic Repeat reQuest). Cette thèse porte sur la transmission de données pour le HSDPA en mode FDD, et l’étude des algorithmes HARQ. Pour augmenter le débit de transmission, la technique MCA adapte la modulation et le rendement de codage au fur et à mesure que les conditions du canal de propagation varient. L’utilisation des modulations d’ordre supérieur (16-QAM) dégrade les performances du récepteur Rake. En plus, avec ce dernier, le simulateur HSDPA demande un temps de calcul très long pour atteindre de bonnes performances. Ceci nous a motivé à introduire une méthode de simulation rapide qui fournit pratiquement les mêmes performances dans un temps de calcul plus réduit. Pour améliorer les performances du MCA avec le récepteur Rake, nous avons implémenté les techniques de retransmission HARQ. Selon l’implémentation et les performances, on distingue deux approches de retransmission : la première est basée sur l’algorithme de Chase où les retransmissions portent la même information que celle portée par la transmission originale, et la deuxième repose sur l’algorithme IR (Incremental Redundancy) dans lequel chaque retransmission transporte une redondance supplémentaire. L’analyse des performances a montré que l’HARQ apporte un gain considérable après seulement 2 transmissions. Cependant, avec les modulations d’ordre supérieur, cette technique peut atteindre ses limites lorsque le canal de transmission induit une interférence multitrajets sévère. Cette limitation nous a amené à introduire une méthode qui combine l’HARQ avec la suppression d’interférence multitrajets (MPIC). Pour améliorer cette technique nous avons proposé d’utiliser la technique de réarrangement de constellation qui apporte une diversité importante en changeant la constellation d’une transmission à l’autre. Nous avons constaté une nette amélioration des performances malgré la présence de trajets multiplesThe major evolution of UMTS (Universal Mobile Telecommunications System) in recent years is the High Speed Downlink Packet Access (HSDPA) which provides data rates up to 10 Mbps. The implementation of HSDPA includes multicode transmission in joint application with Adaptive Modulation and Coding (AMC) as well as Hybrid Automatic Repeat reQuest (HARQ). This thesis deals with the implementation of the HSDPA simulator in FDD (FrequencyDivision Duplex) mode according to 3GPP technical specifications. It also aims to study the HARQ algorithms for HSDPA. The performance of AMC is significantly degraded when higher order modulation (16-QAM) is used in a multipath environnement. Moreover, the HSDPA simulator requires a very long time of computation to provide good performance in multipath channel. In order to solve this problem, we have introduced a simplified simulator which exploits the performance of HSDPA over gaussien channel as look-up tables to compute the block error rate in multipath channel. To make the AMC technique more powerful, we have implemented the HARQ technique. It combines ARQ methods with turbo coding. There are two fundamental approaches for HARQ : the first is Chase approach in which retransmissions are identical to the original transmission, the second approach is IR (Incremental Redundancy) in which the retransmissions carry additionnal redundancy. The performance analysis shows that a significant gain is offered by HARQ after only 2 transmissions. However this technique can exhibit an error floor when using higher order modulation in multipath environnement. As a solution to this limitation, we have employed HARQ technique combined with soft Multipath Interference Cancellation (MPIC). For enhancing this method, we have proposed to use the constellation rearrangement technique which provides additionnal diversity by changing the constellation from one transmission to other. With this techniques, very good performance is offered, and the error floor is mitigated or completely removed
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Sousa, Leonardo Ramon Nunes de. "Avaliação da qualidade de voz do serviço VoIP em sistemas HSDPA". reponame:Repositório Institucional da UFC, 2007. http://www.repositorio.ufc.br/handle/riufc/16076.
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SOUSA, L. R. N. Avaliação da qualidade de voz do serviço VoIP em sistemas HSDPA. 2007. 108 f. Dissertação (Mestrado em Engenharia de Teleinformática) – Centro de Tecnologia, Universidade Federal do Ceará, Fortaleza, 2007.Submitted by Marlene Sousa (mmarlene@ufc.br) on 2016-04-04T17:50:56Z No. of bitstreams: 1 2007_dis_lrnsousa.pdf: 2856245 bytes, checksum: 09d1682db6deab934bb19b5dc67e6098 (MD5)
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In recent years, we can observe the development and fast dissemination of VoIP services, being integrated by the present market, beside conventional telephony and cellular networks. For being a technological alternative that contributes to minimize costs, we see an increasing preference for voice transmission through IP networks. HSDPA, as a cellular system, allows high speed data transmission,increases the network width of band and creates new possibilities for multimedia services, as VoIP that transmits in wideband to mobile telephones. The delay inherent to this system, however, is a challenge for the need to assure good quality of voice transmissions, demanding a considerable effort of analysis of this service.These facts justify a study that focus on the quality of voice in VoIP over HSDPA.To evaluate the voice quality, in this study, we applied MOS method that makes numerical values correspond to categories like quality and intelligibility of transmitted voice, getting these data through objective and subjective methodologies. The evaluation process was divided in fases according to the characteristics of each methodology and to technical recommendations, and was done through dynamic computational simulations. For objective evaluation process,algorithm PESQ was employed to obtain MOS concepts, whereas, for subjective evaluation, voice files with a percentage of error have been placed in Internet for listening and for the attribution of MOS concepts based in the perception of the listener. The results of this research show that both evaluation methods got satisfactory concepts of quality, that QoS is steady and positive in the simulations, that a good quality for the voice files and the probable satisfaction of the users of the VoIP service on cellular system HSDPA is guaranteed for 2% FER rate. Finally, it shows that MOS concepts produced by objective methodology were close enough to those given by subjective evaluation to dispense with the arduous work of making diverse voice files to be heard and subjectively evaluated by a statisticaly valid amount of users.
Nos últimos anos, observa-se o surgimento e a rápida disseminação do serviço VoIP, integrando-se ao mercado atual junto à telefonia convencional e às redes celulares. Por ser uma alternativa tecnológica que contribui para minimizar ustos, assiste-se a uma preferência crescente por fazer fegar a voz através das redes IP. O HSDPA, como sistema celular, permite a transmissão de dados em alta velocidade, aumenta a largura de banda da rede e abre novas possibilidades de serviços multimídia, como o VoIP que utiliza a transmissão em banda larga para telefones móveis. Exige-se, porém, um considerável esforço de análise deste serviço, pois o atraso inerente a esse sistema é um desafio para a garantia de qualidade de voz. Estes fatos justificam, conseqüentemente, um esforço de análise que se detenha sobre a qualidade de voz no VoIP sobre o HSDPA. Para avaliar a qualidade de voz, neste estudo aplica-se o método MOS, que faz corresponder valores numéricos a categorias como medidas de qualidade e inteligibilidade da voz transmitida, obtendo-se esses dados de forma objetiva e subjetiva. O processo de avaliação dividiu-se em etapas de acordo com cada metodologia, seguindo recomendações técnicas e através de simulações computacionais dinâmicas. Na avaliação objetiva, utilizou-se o algoritmo PESQ para obtenção do conceito MOS, enquanto que na avaliação subjetiva, arquivos de voz com certo percentual de erro foram colocados em um endereço na Internet para escuta e atribuição de nota MOS, baseada na percepção do usuário ouvinte. Os resultados mostraram que os dois métodos de avaliação obtiveram conceitos de qualidade satisfatórios, que o QoS nas simulações é estável e positivo, que uma boa qualidade para os arquivos de voz e a provável satisfação dos usuários do serviço VoIP sobre o sistema celular HSDPA é garantida para uma taxa de 2% de FER. Finalmente, mostra-se que a metodologia objetiva garante a obtenção de notas MOS aproximadas da subjetiva, evitando o árduo trabalho de fazerem-se ouvir diversos arquivos de voz por uma quantidade significativa de usuários para ser válida estatisticamente.
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Hadjar, Omar Rachid. "Analyse, implémentation et évaluation de performance de la future méthode d'accès HSDPA". Thesis, Université Laval, 2006. http://www.theses.ulaval.ca/2006/23718/23718.pdf.
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La technologie HSDPA (High Speed Downlink Packet Access) représente la première
étape d’évolution de la méthode d’accès du réseau mobile de troisième génération UMTS
(Universal Mobile Telecommmunications Service). Cette technologie permet d’obtenir
des débits théoriques supérieurs à 10 Mbps sur le lien descendant et de supporter des
services à valeur ajoutée, tels que l’accès Internet à haute vitesse, le téléchargement
de fichiers audio et vidéo, la réception de programmes télévisés et la visiophonie. Ces
améliorations sont rendues possibles grâce à une combinaison de propriétés qui sont à
la base du HSDPA et qui consistent à adapter le codage et la modulation en fonction
des conditions du canal radio (AMC : Adaptative Modulation and Coding), à effectuer
des retransmissions rapides de paquets erronés (HARQ : Hybrid Automatic Repeat ReQuest) et à utiliser des méthodes d’ordonnancement intelligentes plus rapides. Même
si l’introduction de ces nouvelles techniques contribue à une augmentation de la capacité
du système, elle engendre toutefois une plus grande complexité dans l’évaluation
de ses performances dans des conditions réelles. Dans ce contexte, nous proposons une
implémentation et une évaluation de la méthode d’accès HSDPA qui prend en considération
les spécifications techniques des Node B et des terminaux mobiles d’un système
UMTS. Les résultats obtenus de cette implémentation, basés sur plusieurs scénarios
utilisant des données géographiques réelles, montrent que le système réussit à satisfaire
aux exigences des services multimédia.High speed downlink packet access (HSDPA) is an add-on technology for W-CDMA that allows higher downlink data rates and greater base station capacity. With HSDPA, W-CDMA systems, which today are seemingly stuck at 384 kbps, will be able to shift gears and move ahead to so-called 3.5G performance with over 10 Mbps throughput on the downlink. The incorporation of HSDPA in Release 5 of the 3GPP W-CDMA specification is the most significant change on the RF side since Release 99. Advanced techniques such as adaptive modulation and coding (AMC) and hybrid automatic repeat request (HARQ) are used to modify the coding and physical layer parameters adaptively in response to the instantaneous channel quality, thus enabling gains in spectral efficiency and data rates. On the other hand, such improvements also bring a higher complexity degree in the evaluation of the radio subsystem performance. This evaluation is crucial for operators who are willing to provide value-added services with rich multimedia contents. This thesis aims at implementing and simulating a radio access network on a real geographic area using the HSDPA features. Results show that such features enable to satisfy the quality of service requirements needed to support the new data-oriented services.
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Szabo, Andrei [Verfasser]. "Evaluation of MIMO concepts in HSDPA by system level simulations / Andrei Szabo". Aachen : Shaker, 2008. http://d-nb.info/1161309381/34.
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CORREA, RODRIGO JUREMA DE ASSIS. "PERFORMANCE ANALYSIS OF LINKS WITH ADAPTIVE MODULATION APPLIED TO WCDMA/HSDPA SYSTEMS". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2003. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=4273@1.
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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOEste trabalho é um estudo sobre o desempenho de um enlace típico do padrão UMTS/WCDMA para sistemas celulares de terceira geração, utilizando a técnica denominada modulação adaptativa. Esta técnica consiste em escolher, para cada quadro de bits transmitido, a modulação mais adequada às condições do canal. Os aspectos básicos do problema foram formulados analiticamente considerando a transmissão com modulações PSK e QAM coerentes em um canal com desvanecimento plano e efeito Doppler. Para considerar a aplicação a um modelo mais realista, foi desenvolvido um programa de simulação capaz de modelar esse mesmo problema considerando os principais componentes do sistema HSDPA (High Speed Data Packet Access), um sub-sistema do UMTS/WCDMA padronizado para transmissão de dados em alta velocidade no enlace de descida. O desempenho do enlace foi avaliado para diversas situações através da taxa de erro de bit, da taxa de transmissão média e da vazão obtida na transmissão, procurando-se investigar a influência de parâmetros do sistema nesse desempenho.
This work is a study about the performance of a typical UMTS/WCDMA link for third generation mobile communications systems which uses the adaptive modulation technique. This technique consists of choosing, for each transmitted frame, the most efficient modulation according to the channel conditions. The basic aspects of the problem were analytically examined considering transmissions with PSK and QAM coherent techniques in a flat fading channel with Doppler effect. A simulator was developed in order to consider the application in a more realistic model. This simulator was capable of modeling this problem considering the main aspects of the HSDPA (High Speed Data Packet Access) system, which is a subsystem of UMTS/WCDMA that is standardized for high-speed data transmission in the downlink. The link level performance was evaluated for many different situations through average transmission bit error rate and throughput, investigating the influence of the system parameters in this performance.
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RAMOS, MARCELO CORREA. "PERFORMANCE OF ADAPTIVE MODULATION IN WCDMA/HSDPA LINKS IN PRESENCE OF MULTIPATH". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2004. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=5869@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOREste trabalho é um estudo sobre um enlace do sistema HSDPA (High Speed Downlink Packet Access), um subsistema do padrão UMTS/WCDMA, desenvolvido para a transmissão de dados em alta velocidade no enlace de descida. Para atingir altas taxas de transmissão, é prevista a utilização, neste sistema, de diversas técnicas avançadas de processamento de sinais, entre elas a modulação adaptativa. O princípio desta técnica é escolher, para cada quadro de bits transmitido, a modulação mais adequada às condições do canal. Através de simulação, o desempenho da modulação adaptativa em enlaces HSDPA foi avaliado em [4], considerando um canal com desvanecimento plano. Estendendo este trabalho, foram introduzidos novos módulos no simulador, de forma a considerar um canal com multipercursos e a utilização de um receptor Rake. A estimação do canal, utilizada na adaptação, é implementada através da análise do sinal recebido e combinado no receptor Rake. O desempenho do enlace foi avaliado em presença de duplo percurso, para diversas situações, através da taxa de erro de pacote e da vazão obtida na transmissão, procurando-se investigar a influência de parâmetros do sistema e da interferência entre os dois percursos nesse desempenho.
This work is a study about the performance of a HSDPA (High Speed Downlink Packet Access) which is a subsystem of UMTS/WCDMA designed for high-speed data transmission in the downlink. In order to achieve high bit rates, the use of advanced signal processing techniques, including adaptive modulation, is specified. This technique consists of choosing, for each transmitted frame, the most efficient modulation according to the channel condition. The performance of adaptive modulation in HSDPA links in a flat fading channel has been evaluated in [4] through simulation. In the present work, new simulation modules have been developed to consider multipath and a Rake receiver. The channel estimation used in the link adaptation is obtained from the received and combined signal at Rake receiver. The link level performance has been evaluated in a double path channel for different situations through packet error rate and throughput. The influence of system parameters and path interference on the performance has been investigated.
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Husain, Samreen Riaz. "Delay-based packet scheduling for High Speed Downlink Packet Access". Thesis, Kingston, Ont. : [s.n.], 2007. http://hdl.handle.net/1974/649.
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Azizan, A. "Physical layer performance analysis of Satellite High Speed Downlink Packet Access (S-HSDPA)". Thesis, University of Surrey, 2008. http://epubs.surrey.ac.uk/842979/.
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This thesis considers the physical layer performance of the Satellite High Speed Downlink Packet Access (S-HSDPA) system via ground based relays or intermediate Module Repeaters (IMRs). The work evaluates the modifications needed for the terrestrial HSDPA system to a satellite architecture by change of certain significant parameters within a high dispersive IMR environment to deliver high data throughput to satellite mobile terminals. Initial results for S-HSDPA with different terminal capabilities and modulation formats have been obtained. Two diversity techniques, namely receive antenna diversity and space time transmit diversity (STTD) were also investigated. The impact of increasing the number of multicodes transmission for the S-HSDPA system has also been considered. In all of these results, we have shown the capacity to be insufficient to support an economic operational system. In order to investigate improved capacity we have analyzed two advance receiver techniques using channel equalizers and multipath interference cancellers. The performances of two low complexity chip-level adaptive equalizers (CPICH NLMS equalizer and Griffiths' equalizer) equalizer) and the multipath interference canceller (MPIC) have been compared with the conventional RAKE receiver for the S-HSDPA system in an IMR environment. It has been shown that the equalizers can increase the throughput in comparison to the conventional Rake receiver while incurring minimum additional complexity. Thus it is concluded that advanced terminal receivers will be necessary in any practical satellite system. Finally, a study of the orthogonality factor (which parameterizes the intracell interference), as a crucial parameter in the calculation of downlink satellite power has been performed in the IMR environment. Results of the orthogonality factor are presented for multicode S-HSDPA transmission for simple receivers and the use of receive antenna diversity. Using the equalizer based receivers it is shown that the orthogonality factor statistics can be significantly lowered as compared to the conventional matched filter receiver.
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Matinrad, Arash. "Design & development of an HSPA system simulator for network planning". Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-69673.
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HSPA planning requires identification of key performance indicators (KPIs), such as infrastructure cost,performance, service quality and the amount of E/M pollution. To evaluate such a framework describing and linking these key elements for HSPA planning and optimization we need to carry out a set of HSPA system-level event-driven simulations under different scenarios. To have such simulations, a new tool should be developed. In this thesis work a simulation tool is developed within NS-3, an open source network simulator. The simulation tool consists several entities to represent a UMTS network and respective nodes in it, and necessary procedures to form a network dynamically. A simple base station removal algorithm in a system level, is developed focusing on the reduction of capital expenditure (CAPEX) of a network. The algorithm defines a cost function in order to remove the most costly base station from network preserving the target coverage percentage. Baseline results show that the simulation tool is working properly and later the results from algorithm indicate that, it is possible to use the algorithm within a dynamic simulation.
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KANSAU, SILVA IMAD NASIB. "Proprietes fonctionnelles et immunologiques de la chaperonine hspa de helicobacter pylori". Paris 7, 1996. http://www.theses.fr/1996PA077075.
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Helicobacter pylori est une bacterie responsable de gastrites chroniques qui peuvent evoluer vers la maladie ulcereuse, l'atrophie gastrique et les carcinomes gastriques. L'objectif de ce travail a ete de caracteriser la chaperonine hspa (homologue a groes) de h. Pylori sur le plan genetique, moleculaire et immunologique. La caracterisation de l'operon codant pour hspa et hspb (homologue a groel) a revele une organisation similaire a celle des operons groesl d'autres bacteries. Hspa s'est averee unique du fait de la presence, dans sa partie c-terminale, d'une sequence riche en residus histidine. La construction de proteines recombinantes contenant differents fragments de hspa fusionnes a la proteine mbp et l'etude de leur affinite pour divers cations divalents ont permis de demontrer que hspa presente une plus forte affinite pour les ions nickel que pour les autres cations ; la fixation du nickel a lieu sur la partie c-terminale de hspa. La co-expression du gene hspa et des genes ureasiques de h. Pylori chez escherichia coli a confirme le role de hspa dans l'activation de l'urease. Par ailleurs, il a ete montre que hspa est immunogene et que la reponse serique des patients infectes est dirigee principalement contre sa partie n-terminale. Neanmoins, seule une partie des patients infectes produit des anticorps anti-hspa. L'analyse de la sequence en acides amines de la proteine codee par des isolats cliniques a revele l'existence de deux variants antigeniques. Cependant, aucune correlation n'a pu etre observee entre la presence de chacun de ces variants et la production d'anticorps. Enfin, dans un modele murin, hspa augmente les proprietes protectrices de la fraction ureb de la preparation vaccinale. L'ensemble des donnees acquises a permis d'esquisser un premier modele fonctionnel du role de hspa vis-a-vis de l'urease. Les donnees immunologiques presentees ouvrent des perspectives pour la recherche des moyens de protection contre l'infection a h. Pylori
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Fialová, Ivana. "SROVNÁNÍ VYBRANÝCH MOBILNÍCH PŘIPOJENÍ K INTERNETU". Master's thesis, Vysoká škola ekonomická v Praze, 2008. http://www.nusl.cz/ntk/nusl-5289.
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The topic of presented thesis is the subject of mobile Internet connectivity in the Czech Republic. The text is divided into two main parts. The first theoretical part is focused on an individual description of the technologies (GSM, GPRS, EDGE, UMTS and HSDPA) which are being offered in the Czech Republic by the operators. The greatest emphasis is put on a description of UMTS and HSDPA. The second part is practical; it describes the offers of each respective Czech operator focusing on the third-generation network or particularly the network operator with the highest connection speed. The thesis compares current offers against those in the year 2006. The next practical part is aimed at creating a methodology for testing mobile connections and its applications for UMTS and CDMA operator's tariffs at T-Mobile and Telefónica O2. The contribution of this work is to provide a comprehensive picture of a mobile Internet connection in the means of technological background and practical applications.
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Murugesapillai, Navamshan. "The performance of the generalized RAKE (G-RAKE) receiver in a WCDMA-HSDPA scenario". Thesis, University of Ottawa (Canada), 2005. http://hdl.handle.net/10393/26989.
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The High-Speed Downlink Packet Access (HSDPA) is a packet-based data service for increased data speed over WCDMA downlink. At high-speed data rate, advanced receivers are needed to realize a reasonable bit error performance.
This thesis studies the link-level performance of the G-RAKE receiver for the HSDPA and ways to reduce the receiver's complexity. Unlike the conventional RAKE receiver, the G-RAKE receiver suppresses interference caused by frequency-selective fading channels by accounting for coloured noise found in the fingers' output. Thus, G-RAKE optimizes the placement of fingers and the weighting coefficients in the Maximum Likelihood formulation.
In this thesis, performance of the G-RAKE is evaluated via simulations for both static and realistic multipath fading channels described in the literature. According to simulations, G-RAKE receiver compensates for the performance loss experienced by RAKE receivers when the user equipment becomes interference limited.
In G-RAKE receiver, calculating the weighting coefficients, which involves inverting the channel impairment matrix, is an expensive operation. It is shown that the complexity and processing time of this operation and, hence, of the overall receiver can be reduced with the Conjugate Gradient or Preconditioned Conjugate Gradient methods.
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Romero, Zevallos Miguel Félix. "Diseño de una red HSDPA para la ciudad de Arequipa / Miguel Félix Romero Zevallos". Bachelor's thesis, Pontificia Universidad Católica del Perú, 2009. http://tesis.pucp.edu.pe/repositorio/handle/123456789/198.
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El presente proyecto de tesis consiste en realizar el diseño de una red de tercera
generación para la ciudad de Arequipa; para esto se ha decidido utilizar la tecnología HSDPA que evoluciona a partir de la tecnología UMTS. Durante el desarrollo de este proyecto veremos el porqué de la elección de dicha tecnología y analizaremos el mercado de dicha ciudad para ver si es que requiere de la implementación de una red de tercera generación y la rentabilidad de dicha inversión.Tesis
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Bergström, Andreas. "Packet Data Flow Control in Evolved WCDMA Networks". Thesis, Linköping University, Department of Electrical Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-4881.
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The key idea of the new, shared high-capacity channel HSDPA, is to adapt the transmission rate to fast variations in the current radio conditions, thus enabling download peak data rates much higher than what WCDMA can offer today. This has induced a need for data that traverses the mobile network to be intermediately buffered in the Radio Base Station, RBS. A scheduling algorithm then basically selects the user with the most beneficial instantaneous radio conditions for access to the high-speed channel and transmission of its data over the air interface.
The purpose of this thesis is to design a flow control algorithm for the transmission of data packets between the network node directly above the RBS, the RNC, and the RBS. This flow control algorithm should keep the level of the buffers in the RBS on such a level that the air interface may be fully utilized. Yet it is not desirable with large buffers since e.g., this induces longer round-trip times as well as loss of all data in the buffers whenever the user moves to another cell and a handover is performed. Theoretical argumentations and simulations show that both of these requirements may be met, even though it is a balancing act.
Suggested is a control-theoretic framework in which the level in the RBS buffers are kept sufficiently large by taking into account predictions of future outflow over air and by using methods to compensate for outstanding data on the transport network. This makes it possible to keep the buffer levels stable and high enough to fully utilize the air interface. By using a more flexible adaptive control algorithm, it is shown possible to reach an even higher utilization of the air interface with the same or even lower buffering, which reduces the amount of data lost upon handovers. This loss is shown to be even more reduced by actively taking system messages about upcoming handover events into account as well.
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Saker, Louai. "Energy consumption reduction mechanisms in mobile networks". Thesis, Evry, Institut national des télécommunications, 2011. http://www.theses.fr/2011TELE0029.
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La consommation en énergie des réseaux de télécommunications a suscité un intérêt grandissant au cours des dernières années et les opérateurs mobiles cherchent des solutions innovantes pour optimiser l’efficacité énergétique. Dans cette thèse, nous nous focaliserons sur les schémas d’optimisation de la consommation d’énergie des réseaux d’accès mobiles. Nous commençons par étudier la stratégie de partage de charge qui minimise la consommation d’énergie dans la cellule tout en limitant l’impact sur la Qualité de Service. Le gain obtenu par ces algorithmes de gestion des ressources radio reste cependant limité; ceci est dû au fait que la consommation d’énergie ne dépend pas que de la charge, mais comporte une importante partie constante. Pour obtenir un gain plus important, nous proposons la mise en veille de certaines ressources du réseaux aux heures creuses où le trafic est faible, ce qui mène à des gains substantiels. Nous proposons ensuite un contrôleur de gestion de la mise en veille qui choisit l’action optimale en fonction de l’état du réseau. En effet, l’activation d’une nouvelle ressource n’est pas instantanée et un effet ping-pong peut apparaitre suite aux commandes simultanées d’activation/désactivation des ressources. Nous adaptons nos contrôleurs afin de prendre en compte ces imperfections, et nous montrons comment déduire la politique optimale. Nous étudions ensuite le cas de déploiement de petites cellules dans des réseaux hétérogènes et montrons que leur efficacité énergétique est améliorée par rapport au réseau purement macro-cellulaire, pourvu que la consommation d’énergie de petites cellules reste faible. Nous proposons ensuite un contrôleur optimal qui active/désactive les petites cellules en se basant sur des informations de trafic et de localisation des usagers. Nous considérons différents cas de figure avec une information complète, partielle ou retardée et montrons que ces schémas de mise en veille permettent d’atteindre d’importants gains de consommation d’énergieIn the recent years, more importance has been given to the energy consumption issue in telecommunication networks and mobile operators are rethinking their network design for optimizing its energy efficiency. In this thesis, we propose schemes for optimizing the energy consumption of mobile access networks. We begin by proposing energy-aware Radio Resource Management (RRM) schemes and show that a load balancing between available resources gives some energy savings. However, these gains remain small as a large part of the energy consumption is load-independent. We thus propose sleep mode schemes of resources in the network (cells or carriers) and show that they give a large gain when traffic is low. We then propose optimal sleep mode controllers that give, for each traffic scenario, the best actions to take in each state of the network. We make two observations: the first is that activating a new resource is not instantaneous, leading to QoS degradation if a conservative policy is not considered, and the second is that a ping-pong effect may appear at the frontier between two capacity regions. We adapt our controllers to take into account these imperfections, and show how to derive the optimal policy using Markov decision theory. We then extend our works to the case of small cell deployment in heterogeneous networks, composed of macro and small cells base stations. We study the capacity and power consumption of these networks and show that the energy efficiency is increased for some deployment strategies when the power consumption of small cells is low. We then propose sleep mode for small cells and develop optimal sleep/wakeup schemes based on the information on traffic load and user localization in the cell, in the cases where this information is complete, partial or delayed. We show that these sleep mode schemes achieve large energy consumption gains
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Baştuğ, Ahmet. "Développement de récepteurs avancés pour les systèmes de communication mobile de type WCDMA et HSDPA". Paris, ENST, 2006. http://www.theses.fr/2006ENST0007.
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Dans la première partie de la thèse, on considère des méthodes d’estimation des canaux utilisateurs dédiés en liaison descendante. Ces méthodes sont particulièrement avantageuses dans un contexte de transmission à formation de faisceaux. Elles ne supposent aucune connaissance a priori des retards des signaux reçus ainsi que les paramètres de formation des faisceaux; exploitent la totalité des séquences pilotes transmises ainsi que la dynamique structurée du canal. Dans la seconde partie, on commence par considérer un schéma d’égalisation au niveau chip et dite HDD-NLMS. Ce schéma utilise l’estimation de la précédente séquence chip comme réponse cible pour l’adaptation de l’égaliseur. Dans la suite propose les égalisateurs niveau symbole HSDPA N-Griffith et HDD-NLMS qui permettent une vitesse d’adaptation 16 fois plus élevée que dans le cas de l’utilisation des symboles PCPICH. Les solutions spécifiques HSDPA ont une complexité raisonnable et offrent des performances proches aux Max-SINR dans un environnement réel. Dans la dernière partie, nous évaluons l’avantage des égalisateurs au niveau chip par rapport au récepteur Rake conventionnel ainsi que l’avantage d’une décision hard par rapport à l’utilisation d’une contre réaction linéaire dans le contexte d’un récepteur avec élimination itérative parallèle des interférences. Cette contre réaction sera déduite d’un développement polynomial de l’inverse de la matrice de covariance en amont du premier étage d’égalisation. Etant donné que les égalisateurs à chaque étage sont différents, nous utilisons les résultats d’analyse des étages précédents afin de pouvoir estimer les paramètres de l’égalisateur à un étage donnéIn the first part of the thesis, we consider user dedicated downlink channel estimation methods, which are especially beneficial when there is dedicated channel transmit beamforming. The methods do not assume any a priori knowledge of the channel path delays and the beamforming parameters and they exploit all the transmitted pilot sequences as well as the structured dynamics of the channel. In the second part we first consider a chip level HSDPA-specific decision-directed normalized least mean squares (HDD-NLMS) equalization scheme which uses the previous base station chip sequence estimates as the desired responses for equalizer adaptation. Then we propose HSDPA symbol level N-Griffiths and HDD-NLMS equalizers which enable adapting 16 times more frequently than the PCPICH-symbol level adaptation. All the proposed algorithms have reasonable complexity and close to Max-SINR performance in realistic working regimes. In the last part we assess the benefits of using chip equalizers w. R. T. The usage of the conventional Rake receiver and using hard decision or hyperbolic tangent symbol nonlinearities w. R. T. The usage of linear feedback operations in the context of an iterative parallel interference cancellation receiver that we derive from the polynomial expansion of the symbol level covariance matrix inverse after the first stage equalization. Since the equalizers at different stages of the considered interference canceller are to be different as well, in order to estimate the essential equalizer parameters of a particular stage we use the estimates from the preceding stage