Dissertations / Theses on the topic 'WiMAX'
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Муліна, Наталія Ігорівна, Наталия Игоревна Мулина, Nataliia Ihorivna Mulina, and O. P. Ostapenko. "Wimax." Thesis, Видавництво СумДУ, 2010. http://essuir.sumdu.edu.ua/handle/123456789/18431.
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Yasir, Mukhtar Muhammad, and Badar Munir Kamal. "Issues In WiMax Handover." Thesis, Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-1209.
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WiMax, the Worldwide Interoperability for Microwave Access is a new technology dealing with provision of data over long distance using wireless communication method in many different ways. Based on IEEE 802.16 WiMax is claimed as an alternative broadband rather than cable and DSL. In our thesis study we will findout the phenomenon and factors involved in WiMax handover and their effect on overall quality of service. We also intend to look into the solutions possible for those problems effecting WiMax QoS in handover. Handover is the main theme of wireless technolgy and it makes interoperability between diffrent network technologies and provides mobility. However there are some problems during handover and the problem in our focus will be handover delay. Handover delay if longer than expected makes the communication faulty and introduces errors and packet loss which in turns degrade QoS in WiMax
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Булашенко, Андрій Васильович, Андрей Васильевич Булашенко, Andrii Vasylovych Bulashenko, and Ф. Ф. Дубровка. "Анализ возможностей стандарта WIMAX." Thesis, Сумской государственный университет, 2012. http://essuir.sumdu.edu.ua/handle/123456789/29270.
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WiMAX (Worldwide Interoperability for Microwave Access) - это коммерческое “имя” стандарта беспроводной связи 802.16 поддержанного известной промышленной группой.
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Arshad, Awan Muhammad. "WiMAX Traffic Calculations in WRAP." Thesis, Department of Computer and Information Science, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-19941.
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The aim of the thesis is to develop and describe WRAP’s capabilities in handling the WiMAX standard as defined in IEEE 802.16e related to traffic capacity calculations. WRAP International has developed the software WRAP for spectrum management and radio network planning. WRAP includes various technical calculation functions that are applied for design and analysis tasks with the purpose of achieving the desired quality of service within radio communication networks, navigation and radar systems. WRAP already includes functions for radio wave calculations to establish for instance coverage; best server maps etc, as well as traffic calculations for cellular networks (2G) using channel-orientated calculations that are modeled by Erlang B and Erlang C formulas. Since WiMAX supports multiple broadband data services including voice, video, web data, interactive network gaming and streaming media so there is a need to build a tool for the estimation of WiMAX traffic capacity calculations. Some methods and algorithms are analyzed and a tool has been built to ease the network planner’s job. It works based upon the calculations and algorithm presented in the report. Total number of users and data rate supported by a base station is calculated and total number of base stations, required for the coverage of a specific area is determined. This new tool is compatible with WRAP’s current functions.
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Sandhu, Waseem Hussain, and Muhammad Awais. "MULTIPLE ANTENNA TECHNIQUES IN WiMAX." Thesis, Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-1120.
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Now-a-days wireless networks such as cellular communication have deeply affected human lives and became an essential part of it. The demand to buy high capacity and better performance devices and cellular services has been rapidly increased. There are more than two hundred different countries and almost three billion users all over the world which are using cellular services provided by Global System for Mobile (GSM), Universal Mobile Telecommunication System (UMTS), Wireless Local Area Network (WLAN) and Worldwide Interoperability for Microwave Access (WiMAX). In the past decade, one antenna is connected to only one communication radio device at the same time but currently this scenario has been completely changed. To increase the capacity of the channels and to improve the bit error performance between mobile station and service station, it is now possible to connect one antenna with more than one communication radio device at the same time. Multiple Input Multiple Output (MIMO) systems are designed to obtain this requirement. In MIMO systems, antennas are combined in the form of small frames like coupling in cellular devices. Diversity means to obtain successful transmission and reception of radio signals with accordance to polarization and correlation. Due to diversity the capacity of the channels and bit error rate are improved, so diversity is one of the main and important properties of MIMO systems. This thesis is emphasized to study WiMAX systems by implementing multiple antenna techniques, by observing the bit error rate performance and data rate in WiMAX systems using two important and currently widely applied multiple access communication techniques. The research will also elaborate these techniques and explain the basic parameters, operations, mathematical calculations and different relevant observations. The simulation tool used in this research thesis is MATLAB which is also used to illustrate the results with figures and graphs.Nu för tiden trådlösa nätverk såsom cellulär kommunikation har stor påverkan på människors liv och blev en viktig del av det. Kravet att köpa hög kapacitet och bättre utrustning prestanda och mobiltelefoni har snabbt ökat. Det finns mer än två hundra olika länder och nästan tre miljarder användare över hela världen som använder mobiltelefoni som Global System for Mobile (GSM), Universal Mobile Telecommunication System (UMTS), Wireless Local Area Network (WLAN) och Worldwide Interoperability för Microwave Access (WiMAX). Under det senaste decenniet har en antenn ansluten till en kommunikationsradio enhet vid samma tidpunkt, men för närvarande detta scenario har fullständigt förändrats. Att öka kapaciteten av kanalerna och för att förbättra prestandan lite fel mellan mobil station och bensinstationen, är det nu möjligt att ansluta en antenn med mer än en kommunikationsradio enhet samtidigt. Multiple Input Multiple Output (MIMO) system är utformade för att uppnå detta krav. I MIMO-system, antenner kombineras i form av små ramar som kopplingsanordningar i cellulär enheter. Mångfald innebär att få lyckad överföring och mottagning av radiosignaler i enlighet med polarisation och korrelation. På grund av mångfalden kapacitet av kanalerna och bit error rate förbättras, så att mångfald är en av de största och viktigaste egenskaper MIMO-system. Denna avhandling är betonas att studera WiMAX system genom att genomföra flera antenn teknik, genom att observera bitars prestanda felfrekvensen och datahastighet i WiMAX system med hjälp av två viktiga och som för närvarande tillämpas allmänt flera tekniker tillgång kommunikation. Forskningen kommer också att utveckla dessa metoder och förklara de grundläggande parametrarna, operationer, matematiska beräkningar och olika relevanta iakttagelser. Den simuleringsverktyg som används i denna forskning avhandling är MATLAB som också används för att illustrera resultaten med siffror och diagram.
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Shabbir, Noman, and Hasnain Kasif. "Radio Resource Management in WiMAX." Thesis, Blekinge Tekniska Högskola, Avdelningen för signalbehandling, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-1227.
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Today, different types of cellular networks are actively working on the radio links. For instance, the Global System for Mobile Communication (GSM) is being used in nearly two hundred countries and currently it has around two and half billion users all over the world. Universal Mobile Telecommunication System (UMTS) is currently deployed in many countries and it is providing increased data rates, coverage and mobility as compared to GSM. Wireless Local Area Networks (WLAN) are very famous when we have a small area and none real time services. Worldwide Interoperability for Microwave Access (WiMAX) is a new technology and it is in deployment phase. In all these cellular technologies, we have very limited recourses and we have to make best use of them by proper management. Radio Resource Management (RRM) is a control mechanism for the overall system which is being used to manage radio resources in the air interface inside a cellular network. The main objective is to utilize the available spectral resources as efficiently as possible. Our aim is to use them in the best possible way to maximize the performance and spectral efficiency in such a way that we have maximum number of users in our network and Quality of Service (QoS) is up to the mark. In a cellular communication system, a service area or a geographical region is divided into a number of cells and each cell is served by an infrastructure element called the base station which works through a radio interface. The frequency license fees, real estate, distribution network and maintenance are the issues which dominates the cost for deploying a cellular network. Management of radio related resources is a critical design component in cellular communications. In RRM, we control parameters like Radio Frequency (RF) planning, link budgeting, modulation schemes, channel access schemes etc. RF planning includes cell planning, coverage of the network and capacity of the network. Our main focus in this thesis will be on cell planning and link budgeting and we will discuss them in context of a WiMAX network.
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Ho, Kenneth T. "Uplink channel estimation in WiMAX." College Park, Md. : University of Maryland, 2008. http://hdl.handle.net/1903/8214.
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Thesis (M.S.) -- University of Maryland, College Park, 2008.Thesis research directed by: Dept. of Electrical and Computer Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Díaz, Meza Gonzalo Alejandro. "Troubleshooting para Tecnologías de Acceso Emergentes." Tesis, Universidad de Chile, 2006. http://repositorio.uchile.cl/handle/2250/104448.
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Esta memoria tiene como objetivo general crear esquemas de troubleshooting para tecnologías de acceso, en particular, para la tecnología Ethernet y para WiMAX, que corresponde a una tecnología inalámbrica que está entrando en el mercado como una buena alternativa para los proveedores de servicios. Para complementar el trabajo en WiMAX se estudian distintos tipos de enlaces inalámbricos, en donde las fallas son similares sobre todo en la capa física.
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Dziyauddin, Rudzidatul Akman. "Quality of service in WiMAX networks." Thesis, University of Bristol, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556715.
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Quality of Service (QoS) and performance issues relating to WiMAX are the key research areas investigated within this thesis. Scheduling and downlink (DL) resource allocation techniques are proposed to develop the QoS in WiMAX since the WiMAX standard does not specify which types of scheduling and DL resource allocation schemes can be employed. An investigation of the WiMAX system using a single antenna and multiple antenna techniques, Space Time Block Code (STBC) 2x2 and Spatial Multiplexing (SM) 2x2, is performed to understand how these transmission schemes are able to improve the system performance. Results of the maximum good put values are validated with the theoretical data rates and the maximum values observed are between 94.5% and 97.0% of the theoretical values. The difference approximately matched the calculated MAC/IP/UDP overheads. The impact of certain realistic scenarios, such as multiple connections, multiple users and a variety of outbound schedulers, on the maximum achievable goodput is also examined. Results with current schedulers show long packet latency, above 100 ms (i.e. 0.1 s), for different number of users in heavy load scenarios, which may not be suitable for real-time applications. Since the present schedulers do not meet the latency requirements, a channel- and delay- aware scheduler is designed to guarantee the required QoS parameter for maximum latency while optimising system achievable good put for real-time applications. Greedy-Latency, a modified Greedy-based scheduler, considers three different aspects together: packet latency, time-varying channel conditions and packet dropping policy. It is found that the maximum latency of 50 ms is guaranteed and thus this packet dropping policy is adopted and evaluated with several leading schedulers. Results also show that Greedy-Latency has the lowest number of dropped packets and the Proportional Fair (PF) scheduler maintains its fairness behaviour even with the dropping policy. Efficiency of radio resource allocation is very important, and there is a strong interplay between channel-aware schedulers and resource allocation. To explore this dynamic resource allocation in WiMAX, Dynamic Power Burst Mapping (DyPBM) is proposed for downlink transmission. The aim is to improve system goodput by considering both the user's subchannel qualities and frame utilisation, and hence two types of burst mapping mechanisms are applied. ->- '" .••.• .,. .•. ' , Because of a rectangular data region, as specified in the WiMAX standard, the exploitation of the users' subchannel conditions, as taken into account by the DyPBM is unable to increase the system good put. Nevertheless, when the frames are assumed fully utilised, the DyPBM numerically outperforms other techniques by up to 0.5 Mbps.
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Moraes, Leonardo Bastos. "Antenas impressas compactas para sistemas WIMAX." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/3/3142/tde-26122013-161125/.
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Alcançar altas taxas de dados em comunicações sem fio é difícil. Altas taxas de dados para redes locais sem fio tornou-se comercialmente um sucesso por volta do ano de 2000. Redes de longa distância sem fio ainda são projetados e utilizados principalmente para serviços de voz em baixas taxas. Apesar de muitas tecnologias promissoras, a realidade de uma rede de área ampla que atenda muitos usuários com altas taxas de dados e largura de banda e consumo de energia razoáveis, além de uma boa cobertura e qualidade no serviço ainda é um desafio. O objetivo do IEEE 802.16 é projetar um sistema de comunicação sem fio para obter uma internet de banda larga para usuários móveis em uma área metropolitana. É importante perceber que o sistema WIMAX tem que enfrentar desafios semelhantes aos existentes sistemas celulares e seu desempenho eventual será delimitado pelas mesmas leis da física e da teoria da informação. Em muitas áreas da engenharia elétrica, tem-se direcionado atenção à miniaturização de componentes e equipamentos. Em particular, antenas não são exceções. Desde que Wheeler iniciou estudos sobre os limites fundamentais de miniaturização de antenas, o assunto tem sido discutido por muitos estudiosos e várias contribuições nesse sentido foram feitas desde então. Os avanços das últimas décadas na área de microeletrônica permitiram a miniaturização dos demais componentes empregados no desenvolvimento de equipamentos eletrônicos e disponibilizaram o uso de aparelhos compactos, leves e com diversas funcionalidades e aplicações comerciais. No entanto, ainda que a integração de circuitos seja uma realidade, a integração completa de um sistema de comunicação sem fio, incluindo a antena, é ainda um dos grandes desafios tecnológicos. No caso de antenas impressas procura-se continuamente desenvolver antenas que, além de compactas, apresentem maior largura de banda, ou operação em múltiplas bandas dada sua inerente característica de banda estreita em projetos convencionais. Neste trabalho, o foco está na miniaturização de antenas impressas através da aplicação de fractais. São apresentadas comparações entre antenas fractais quadradas de Minkowski e fractais triangulares de Koch. Inicialmente, antenas 6 impressas com geometrias convencionais quadradas e triangulares foram projetadas para ter a mesma frequência de ressonância. Depois disso, as estruturas fractais de Minkowski Island e Koch Loop foram implementadas nas antenas quadrada e triangular, respectivamente, até a terceira iteração. As frequências escolhidas foram as de 2,4 GHz, 3,5 GHz, 5,0 GHz e 5,8 GHz. Diversos protótipos foram construídos em dois substratos de permissividade diferentes, o FR-4 e o DUROID 5870. Para validar os resultados foram construídas antenas na frequência de 3,5 GHz para as geometrias quadrada e triangular e suas iterações fractais. A contribuição deste trabalho está na análise sobre as vantagens e desvantagens de cada uma das estruturas propostas. Dependendo dos requisitos de um projeto, a opção pode ser por antenas miniaturizadas com maior largura de banda, como normalmente acontece em alguns projetos comerciais. Entretanto, o interesse por bandas estreitas muitas vezes pode ser um requisito, principalmente para emprego militar, onde por vezes a máxima discrição na transmissão é uma exigência. Além disso, também foi feita uma análise sobre as geometrias que atingiram maior miniaturização.Achieving high data rates in wireless communication is difficult. High data rates for wireless local area networks became commercially successful only around 2000. Wide area wireless networks are still designed and used primarily for low rate voice services. Despite many promising technologies, the reality of a wide area network that services many users at high data rates with reasonable bandwidth and power consumption, while maintaining high coverage and quality of service has not been achieved. The goal of the IEEE 802.16 was to design a wireless communication system processing to achieve a broadband internet for mobile users over a wide or metropolitan area. It is important to realize that WIMAX system have to confront similar challenges as existing cellular systems and their eventual performance will be bounded by the same laws of physics and information theory. In many areas of electrical engineering, miniaturization has been an important issue. Antennas are not an exception. After Wheeler initiated studies on the fundamental limits for miniaturization of antennas, this subject has been extensively discussed by several scholars and many contributions have been made. The advances of recent decades in the field of microelectronics enabled the miniaturization of components and provided the use of compact, lightweight, equipments with many features in commercial applications. Although circuit integration is a reality, the integration of a complete system, including its antenna, is still one of the major technological challenges. In the case of patch antennas, the search is for compact structures with increased bandwidth, due to the inherent narrowband characteristic of this type of antenna. In this work the focus is on a comparison between the Minkowski and the Koch Fractal Patch Antennas. Initially, patch antennas with conventional square and triangular geometries were simulated to present the same resonance frequency. After that, fractal Minkowski and Koch Island Loop antennas were implemented in the square and triangular geometries, respectively, to the third iteration. A comparison was made for two substrates of different permittivities FR-4 and DUROID 5870 at the frequencies of 2,4 GHz; 3,5 GHz; 5,0 GHz and 5,8 GHz. 8 Prototype antennas were built using FR-4 and DUROID 5870 to resonate at a frequency of 3,5 GHz to validate simulation results. The contribution of this work is the analysis of the advantages and disadvantages of each proposed fractal structure. According to the project requirements, the best option can be use a miniaturized antenna with a wider band, as in commercial projects. Particularly in military applications, a narrow band antenna can be a requirement, as sometimes maximum discretion in transmission is a paramount. An additional analysis was performed to verify which of the geometries fulfilled the miniaturization criteria of Hansen.
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Nguyen, Huu Quynh. "Réseaux sans fils hybrides WiFi-WiMax." Paris, ENST, 2008. http://www.theses.fr/2008ENST0068.
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Dans le contexte du développement des technologies sans fils, la technologie IEEE 802. 11a connu un vif succès sous le nom commercial de WiFi. Les nouveaux standards IEEE 802. 16 récemment publiés donnent naissance à une technologie nommée WiMax encore plus performante que le WiFi en terme de capacité et de couverture. Afin d'introduire une nouvelle technologie sans fils sur le marché, l'approche des réseaux hybrides est prometteuse. Cette approche attire l'attention autant du côté académique que du côté industriel car elle permet de combiner les avantages des deux technologies WiFi et WiMax, à savoir un débit élevé, un support multi-service, une large couverture, un déploiement rapide, une grande flexibilité. Dans le cadre de cette thèse, nous introduisons l'architecture d'un réseau sans fils hybride présentant trois niveaux hiérarchiques. Les utilisateurs se situant au niveau 1 se connectent aux points d'accès WiFi qui se trouvent au niveau 2. Ces derniers se connectent à la station WiMax qui se trouve au niveau 3. On suppose que les stations WiMax sont déployées de manière régulière tandis que les points d'accès WiFi sont placés de manière aléatoire. Nous nous sommes concentrés sur le dimensionnement et sur l'optimisation de la couverture selon les paramètres aléatoires. Notre cadre de travail concerne plusieurs types de fonction économique qui tiennent compte des contraints à respecter. L'optimisation de tel réseau se résume à la recherche des optimums des fonctions économiques. Grace à notre analyse statistique et notre outil de simulation, nous pouvons optenir les optimums de ces fonctions afin de determiner la configuration optimale de tels réseauxThe IEEE 802. 11 technology has had a major success in the market place under the name WiFi. Recently, the new IEEE 802. 16 standards have been released promising a wireless technology called WiMAX that is even more efficient in terms of coverage and capacity than WiFi. To introduce this new broadband wireless technology into the market, hybrid wireless networks seem to be a good solution which is receiving a lot of attention in the academic field as well as in industrial domain. As a matter of fact, this solution allows combining all advantages of the two technologies, such as high speed network, multi-services support, high range of coverage, rapidity of deployment, flexibility of system lower infrastructure costs. In this thesis, we have introduced an architecture for hybrid wireless networks in which the network is organized in three hierarchical levels. The users are present in level one, which connects to WiFi access points in level two ; the latter in turn connects to the WiMAX base stations in level three. The WiMAX base stations are supposed to be deployed in regular pattern and the WiFi access points are supposed to be randomly placed. We focus on the dimensioning and parameter optimization problems. We introduce a framework consisting of several economic functions which takes into account all basic trade-offs ; optimizing the network then becomes equivalent to finding the optimum of these economic functions. Our simulation and numerical results assessed the behavior of these economic functions. Based on our analysis and simulation, the optimum of the economic function can be derived to obtain an optimum configuration of the hybrid network
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Ogunleye, Babatunde Samuel. "WiMAX spectrum virtualization and network federation." Doctoral thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/27011.
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Spectrum management in wireless broadband networks as regards its cost and its efficient usage has posed a huge challenge for mobile network operators. Traditionally, network operators had exclusive rights to access the band of spectrum allocated to them, but with the high price of spectrum license, it is becoming necessary to find alternative ways to use and access spectrum more efficiently. Resource virtualization is a method which has been extensively adopted in hardware computing for creating abstract versions of physical hardware resources and it has proven to be a powerful technique for customized resource provision and sharing. This idea of resource virtualization is gradually being transferred into the domain of wireless mobile network resource management but the ideas around it are still evolving. Since spectrum is an important wireless network resource, it is imperative to provide an efficient and cost effective means for the resource to be accessed and utilized. Therefore the idea of spectrum virtualization is investigated in this research as a possible solution to this problem. To expand on the notion of spectrum virtualization, this research further explores the idea of network federation. Network Federation involves the interconnection of diverse network components to be operated as a single seamless network. This will enable them share their network resources while the networks are geographically dispersed and managed by different network operators. To fully implement these concepts there is a need for a well-developed network framework. This research proposes two novel architectures for spectrum virtualization and network federation using the WiMAX (Worldwide Interoperability for Microwave Exchange) wireless broadband technology. The proposed WiMAX spectrum virtualization architecture introduces a novel entity known as the Virtual Spectrum Hypervisor (VS-Hypervisor). This VS-Hypervisor bears the responsibility of spectrum management and virtualization within the WiMAX framework. In the implementation of WiMAX network federation, the novel architecture enables the cooperative existence of multiple WiMAX base-stations having virtualization capabilities with overlapping cellular coverage areas for the purpose of sharing their spectrum resources. In this architecture, a novel federation control plane known as the Virtual Spectrum Exchange Locale (VSEL) is proposed. The VSEL facilitates the VS-Hypervisors in the federated physical base-stations to be able to negotiate and exchange spectrum between themselves to match their spectrum needs. The architectures for WiMAX spectrum virtualization and network federation was modelled and implemented using the OPNET Modeler. Results obtained validated their efficacy with respect to the effective management of the wireless network spectrum. Therefore this proposed network architectures would help network operators optimize their radio networks.
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Melo, Márcio Daniel Tavares de. "Desempenho de redes WiMAX com mobilidade." Master's thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/1989.
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Mestrado em Engenharia Electrónica e TelecomunicaçõesCom a crescente evolução das tecnologias sem fios e a grande necessidade de estarmos sempre on(line) em qualquer lugar veio culminar com o desenvolvimento de uma nova norma a IEEE802.21, pelo grupo IEEE. Esta norma visa optimizar os handovers entre as diferentes tecnologias através de mecanismos e de eventos normalizados, com o objectivo de tornar as diferentes tecnologias transparentes para as camadas superiores. Esta dissertação apresenta mecanismos de mobilidade independentes entre algumas tecnologias sem fios, em especial a tecnologia WiMAX com suporte para mobilidade e a tecnologia WiFi. É descrita a forma como se processam os handovers de redes heterogéneas com base na norma IEEE802.16 e IEEE802.21 e são propostas algumas modificações. Posteriormente é analisado o simulador de redes, o qual foi utilizado para avaliar o desempenho dos handovers em redes heterogéneas através dos novos mecanismos definidos e propostos, e são efectuadas alterações para suportar a sinalização e funcionalidades especificadas. Nesta Tese são simulados vários cenários com handovers de intra-tecnologia e de inter-tecnologia a fim de se obterem parâmetros de desempenho. Os resultados obtidos com as alterações produzidas no simulador mostram que esta nova norma e o mecanismo proposto de integração com as tecnologias 802.11 e 802.16, trazem melhorias significativas nos tempos de handover, assim como no suporte de QoS. ABSTRACT: With the growing trend of wireless technologies and the great need of being always on (line) and anywhere culminate with the development of a new standard the IEEE802.21, by the IEEE group. This standard is designed to streamline the handovers between different technologies through normalized mechanisms and events, with the purpose of making the different technologies seamless to the upper-layers This thesis presents mobility mechanisms independent of the wireless technologies at this stage, particularly WiMAX technology with support for mobility and the WiFi technology. It is described how are processed heterogeneous handovers based on IEEE802.16 standard and the IEEE802.21 and are purposed some changes on it. It is then analyzed the network simulator, which was used to assess the performance of the handovers in heterogeneous networks through the new mechanisms established and purposed, and changes are made to support the signalling and features specified. On this Thesis are simulated several scenarios with handovers of intratechnology and inter-technology in order to obtain performance parameters. The obtained results with the changes produced in the simulator show that this new standard and the purposed mechanism of integration with the technologies 802.11 and 802.16, bring significant improvements on the time of handovers as well as on the support of QoS.
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Matos, Ricardo Jorge Magalhães de. "Suporte de mobilidade em redes WIMAX." Master's thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/1992.
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O desenvolvimento crescente da Internet, com novos serviços e
aplicações que requerem elevadas exigências a nível de qualidade de
serviço, como por exemplo, o VoIP e IPTV, a crescente necessidade de
um utilizador estar sempre contactável em qualquer sítio e a qualquer
momento, torna necessária a integração actual da Internet com as redes
móveis da próxima geração.
A tecnologia IEEE 802.16 surge como uma tecnologia de banda larga
sem fios que pode ter um papel fundamental num ambiente de próxima
geração. Devido aos seus baixos custos de instalação e à possibilidade de
chegar facilmente a zonas rurais ou a zonas de difícil acesso, torna-se um
sério candidato para suprir as necessidades dos utilizadores.
A necessidade de mobilidade pelo utilizador, para aceder a diversos
serviços em diferentes sítios ou ser identificado remotamente para a
posterior recepção de informação também é um desejo futuro.
O protocolo IEEE 802.21 surge como um meio que providencia a
optimização de handover entre diferentes tecnologias de acesso, quer
sejam elas WiFi, WiMAX, 3GGP ou 3GPP2, no sentido de proporcionar
ao utilizador a utilização de diferentes serviços de uma forma
transparente à tecnologia de acesso, quando em situações de mobilidade.
Esta dissertação apresenta a arquitectura desenvolvida para proporcionar
a correcta avaliação da atribuição de QoS e mobilidade transparente,
num ambiente real de próxima geração. Serão também efectuados testes
com o equipamento WiMAX disponível, no sentido de mostrar o seu
correcto comportamento na atribuição de QoS fim-a-fim em cenários
ponto-a-ponto e ponto-a-multiponto com serviços com características de
tempo real. A integração do software da primeira fase do projecto
WEIRD e o seu correcto comportamento em ambientes de atribuição de
QoS também vai ser estudado. A implementação dos diferentes módulos,
em especial a implementação da unidade central da arquitectura de IEEE
802.21 (MIHF), vai ser descrita, no sentido de avaliar o desempenho do
WiMAX e do protocolo IEEE 802.21 numa rede real no âmbito da
segunda fase do projecto WEIRD. Os resultados obtidos demonstram
que a arquitectura desenvolvida consegue fornecer QoS fim-a-fim com
suporte de mobilidade entre redes heterogéneas.
ABSTRACT: The growing development of the Internet, with new services and
applications that require a high level of quality of service, such as, VoIP
and IPTV, the increasing need for a user to be always reachable
anywhere and at anytime, motivates the integration of current Internet
with the next generation of mobile networks.
The IEEE 802.16 technology emerges as a technology for broadband
wireless access that may have a key role in a next generation
environment. Due to its low costs of installation and its ability to easily
reach rural areas or areas with difficult access, it becomes a serious
candidate to supply the needs of users.
The mobility’s necessity by the user, to access to several services in
different locations or be identified remotely for subsequent receipt of
information, is also a future desire.
The IEEE 802.21 protocol provides the optimization of handover
between heterogeneous networks, such as WiFi, WiMAX, 3GGP or
3GPP2, to offer the user different services in a transparent manner to his
access technology, when in situations of mobility.
This Thesis presents the architecture developed to provide the correct
integration of QoS and seamless mobility, in a real next generation
environment. It will also present tests carries out with the available
WiMAX equipment, to show its correct behaviour in the allocation of
end-to-end QoS in point-to-point and point-to-multipoint scenarios with
real-time services. The integration of software from the first phase of the
WEIRD project and its correct behaviour in environments of QoS
allocation will also be studied. The implementation of the various
modules, in particular the implementation of the central unit of IEEE
802.21 architecture (MIHF), will be described, to evaluate the
performance of WiMAX and IEEE 802.21 protocol in a real network
provided by the second phase of the WEIRD project. The obtained
results show that the developed architecture is able to provide end-toend
QoS with seamless mobility support over heterogeneous networks.
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Monteiro, João Diogo Mamede. "Quality of service in WiMAX networks." Master's thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/2029.
Full textAbstract:
Mestrado em Engenharia Electrónica e TelecomunicaçõesO acesso à banda larga é um requisito importante na actualidade para satisfazer os utilizadores em termos de novas aplicações e serviços em tempo real. O WiMAX, como tecnologia sem fios para áreas metropolitanas, prometendo cobrir uma maior superfície e com maior débito, é uma tecnologia promissora para as redes de próxima geração. No entanto um requisito importante para a instalação e massificação desta tecnologia é o seu comportamento a nível de qualidade de serviços e garantia aos utilizadores do cumprimento eficiente dos requisitos de QoS. Esta tese aborda e estuda o suporte de qualidade de serviços para redes WiMAX presente em diferentes modelos de simulação, implementados na ferramenta de simulação ns-2. Para além da validação e comparação entre os modelos existentes, também é efectuada a especificação e implementação de uma solução de QoS composta por um classificador e escalonador, e é proposto e avaliado um algoritmo de escalonamento que utiliza prioritização de classes de serviço e informação física dinâmica “cross layer” para decisões de escalonamento no simulador. Para validar e avaliar as soluções propostas e desenvolvidas, um conjunto de cenários orientados para a utilização de vários serviços e aferição de métricas de QoS foram simulados. Os resultados obtidos mostram a diferenciação entre distintas classes de tráfego. O mecanismo proposto apresenta um pequeno ganho em débito e latência comparativamente às soluções previamente analisadas/implementadas. ABSTRACT: Broadband access is an important requirement to satisfy user demands and support a new set of real time services and applications. WiMAX, as a Broadband Wireless Access solution for Wireless Metropolitan Area Networks, covering large distances with high throughputs, is a promising technology for Next Generation Networks. Nevertheless, for the successful deployment and massification of WiMAX based solutions, Quality of Service (QoS) is a mandatory feature that must be supported. In this thesis , the QoS support for WiMAX in ns-2 simulation software is addressed. A QoS framework, composed by a packet classification mechanism and a scheduler, has been specified and implemented on the simulator, providing service differentiation over WiMAX networks. Furthermore, validation and comparison of different IEEE 802.16 simulation models is provided. Finally a scheduling solution is proposed and evaluated that uses prioritization and dynamic cross layer information for schedulling decisions in WiMAX networks. In order to validate the developed solutions, a set of QoS oriented scenarios have been simulated and the obtained results show that the implemented schedullers are able to efficiently differentiate between the different traffic classes and achieve gains in throughput and delay.
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Araújo, Marco Paulo Viegas. "Planeamento e dimensionamento de redes WIMAX." Master's thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/1993.
Full textAbstract:
Mestrado em Engenharia Electrónica e TelecomunicaçõesO mundo das telecomunicações encontra-se em constante evolução. Perante um mundo cada vez mais globalizado, cabe às telecomunicações a missão de aproximar pessoas que se encontram espalhadas pelo mundo. Quando outrora existiam os telefones fixos (que já em si faziam uma diferença abismal na vida das pessoas), agora temos computadores com Internet o que permite a comunicação com pessoas no outro lado do planeta através de um simples clique no rato, aumentando a eficiência e diminuindo custos. No entanto as pessoas cada vez são mais exigentes e nunca estão satisfeitas com a tecnologia actual, criando assim a necessidade de inovar e ir sempre mais além na área das telecomunicações. Nos últimos 15 anos deu-se um passo de gigante nesta área através das comunicações móveis (especialmente a partir do aparecimento do GSM). Há alguns anos atrás surgiu a tecnologia wireless (sem fios) que trouxe consigo a possibilidade do utilizador estar sempre ligado em (quase) qualquer lugar. No entanto devido a limitações de velocidade, bem como de segurança, existe a necessidade de criar uma nova geração desta tecnologia. Esta nova tecnologia designa-se por WiMAX e prevê-se que mude a vida de muita gente, pois possui débitos elevadíssimos e um bom sistema de segurança. Baseia-se na mesma arquitectura de um vulgar sistema de comunicações móveis: uma estação base por célula (pequena parcela de área) para transmissão dedados e um dispositivo móvel com uma antena para recepção e transmissão de dados e tem como principal vantagem o facto de não possuir fios e permitir que pessoas que vivam em zonas rurais se possam ligar à Internet com débitos elevados. Actualmente esta tecnologia encontra-se em fase experimental, sendo no entanto já implementada em algumas zonas pela primeira vez, nomeadamente em Aveiro, Portugal. Esta dissertação tem como objectivo estudar todo o conceito de “tecnologia WiMAX” e as suas características mais importantes e realizar uma análise séria e profunda do planeamento duma rede baseada nesta tecnologia, recorrendo para isso à ferramenta de simulação ATDI ICS Telecom.
The world of telecommunications is in a constant evolution. In a world that gets more globalized everyday, it’s up to the telecommunications to join people across the globe. In the past we had fixed telephones (which already made a huge difference in people’s lives), but now we have Internet, which allowed us to communicate with people in the other side of the world just by click a mouse button, increasing efficiency and decreasing costs. Still people’s demands are increasing day-by-day and they’re never pleased with the current technology, which results in a bigger necessity to innovate and go further in the telecommunications world. In the last 15 years, a huge step has been taken in the mobile communications (especially since the development of GSM). A few years ago the wireless technology brought the possibility of always being connected (almost) everywhere. Nevertheless, due to speed and security limitations, the needs to develop a better mobile technology as come. This new technology as a name: WiMAX. It is expected to change the life of many persons, due to his high speed and great security system. It is based on the same architecture as a normal mobile system: one base station per cell (small amount of area) to transmit data and a mobile device with an antenna to receive and transmit data and it’s biggest advantage is that it is wireless and allowed people in rural environments to connect to the Internet at a high speed rate. Currently this technology is in an experimental phase, although it’s already being implanted in some regions by the first time. This thesis has a primary goal the study of the WiMAX technology (including it’s most important features) and to made a serious analysis of the planning of a network of this kind (using for that the ATDI ICS Telecom tool).
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Costa, André Amaral. "Assessing WiMAX for vehicular communications applications." Master's thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/1952.
Full textAbstract:
Mestrado em Engenharia Electrónica e TelecomunicaçõesOs acidentes rodoviários têm um enorme impacto na sociedade, quer devido às perdas humanas daí resultantes quer devido aos custos económicos a si associados. Por todo o mundo, esta situação levou ao estudo de mecanismos que permitem aumentar a segurança nas estradas. Por exemplo, na Europa estão a ser financiados vários projectos para desenvolver estes mecanismos e a maior parte das iniciativas em curso requerem a possibilidade dos veículos comunicarem entre si e/ou com estações que se encontram fixas junto à estrada. Devido aos requisitos de mobilidade dos veículos, as tecnologias de comunicação sem fios têm um papel crucial neste tipo de aplicações. Neste sentido, esta dissertação avalia a adequação da tecnologia de comunicação sem fios WiMAX para a transmissão de serviços de segurança rodoviária e/ou outros, entre os veículos e a infraestrutura, usando para isso os mecanismos integrados de diferenciação de tráfego desta mesma tecnologia de comunicação. Especificamente, o objectivo é avaliar se estes mecanismos são apropriados para fornecer os serviços atrás mencionados tendo em conta os seus requisitos tempo-real (largura de banda, latência, variação da latência, etc.).
Road accidents have a huge impact on the society, both because of the resulting human life losses and injuries as well as because of the associated economic costs. This situation fostered the study of mechanisms for increasing road safety all over the world. In Europe, several projects are being funded to develop such mechanisms. Many of the approaches that are being pursued require the ability of the vehicles to communicate with each other and/or with fixed roadside equipments. Due to the mobility constraints, wireless technologies have a crucial role in this kind of applications. This dissertation assesses the suitability of the WiMAX wireless technology for supplying vehicle to infrastructure road safety services and others, using this communication technology integrated quality of service mechanisms that provides traffic differentiation. Specifically, the purpose is to evaluate if these mechanisms are appropriate to provide the referred services taking in account their real-time requirements (bandwidth, latency, jitter, etc.).
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Kleynhans, Waldo. "On channel estimation for mobile WiMAX." Diss., Pretoria : [s.n.], 2008. http://upetd.up.ac.za/thesis/available/etd-01262009-102433/.
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Soundararajan, Srivathsan Agrawal Prathima. "Scheduling in WiMAX based wireless networks." Auburn, Ala, 2008. http://hdl.handle.net/10415/1449.
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Nsoh, Stephen Atambire. "Resource allocation in WiMAX mesh networks." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Mathematics and Computer Science, c2012, 2012. http://hdl.handle.net/10133/3371.
Full textAbstract:
The IEEE 802.16 standard popularly known as WiMAX is at the forefront of the technological
drive. Achieving high system throughput in these networks is challenging due to
interference which limits concurrent transmissions. In this thesis, we study routing and link
scheduling inWiMAX mesh networks. We present simple joint routing and link scheduling
algorithms that have outperformed most of the existing proposals in our experiments. Our
session based routing and links scheduling produced results approximately 90% of a trivial
lower bound.
We also study the problem of quality of service (QoS) provisioning in WiMAX mesh
networks. QoS has become an attractive area of study driven by the increasing demand
for multimedia content delivered wirelessly. To accommodate the different applications,
the IEEE 802.16 standard defines four classes of service. In this dissertation, we propose a
comprehensive scheme consisting of routing, link scheduling, call admission control (CAC)
and channel assignment that considers all classes of service. Much of the work in the
literature considers each of these problems in isolation. Our routing schemes use a metric
that combines interference and traffic load to compute routes for requests while our link
scheduling ensures that the QoS requirements of admitted requests are strictly met. Results
from our simulation indicate that our routing and link scheduling schemes significantly
improve network performance when the network is congested.ix, 77 leaves : ill. ; 29 cm
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Gulzar, Muhammad Atif, Rashid Nawaz, and Devendra Thapa. "Implementation of MIMO-OFDM System for WiMAX." Thesis, Linnéuniversitetet, Institutionen för datavetenskap, fysik och matematik, DFM, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-12221.
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Error free transmission is one of the main aims in wireless communications. With the increase in multimedia applications, large amount of data is being transmitted over wireless communications. This requires error free transmission more than ever and to achieve error free transmission multiple antennas can be implemented on both stations i.e. base station and user terminal with proper modulation scheme and coding technique. The 4th generation of wireless communications can be attained by Multiple-Input Multiple-Output (MIMO) in combination with Orthogonal Frequency Division Multiplexing (OFDM). MIMO multiplexing (spatial multiplexing) and diversity (space time coding) having OFDM modulation scheme are the main areas of focus in our thesis study. MIMO multiplexing increases a network capacity by splitting a high signal rate into multiple lower rate streams. MIMO allows higher throughput, diversity gain and interference reduction. It also fulfills the requirement by offering high data rate through spatial multiplexing gain and improved link reliability due to antenna diversity gain. Alamouti Space Time Block Code (STBC) scheme is used with orthogonal designs over multiple antennas which showed simulated results are identical to expected theoretical results. With this technique both Bit Error Rate (BER) and maximum diversity gain are achieved by increasing number of antennas on either side. This scheme is efficient in all the applications where system capacity is limited by multipath fading.
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Tukkensæter, Brage Rønning. "User Friendly Access Solutions for Mobile WiMAX." Thesis, Norwegian University of Science and Technology, Department of Telematics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9909.
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Today, WiMAX networks are deployed several places worldwide. To get access to these networks, users have to buy equipment specialized for one operator with a subscription. User equipment has earlier been stationary or mounted, but with the Mobile WiMAX amendment, smaller receivers are made possible. Mobile WiMAX allows users to move between different operators, making user access and roaming a more challenging task. In this thesis, several Mobile WiMAX access solutions are discussed, emphasizing security and user friendliness. A captive portal solution is developed, and an EAP-TTLS (Extensible Authentication Protocol - Tunneled Transport Layer Security) solution utilizing FreeRADIUS is planned. Security in WiMAX is compared to Wi-Fi very good. Even in an open WiMAX network traffic can be encrypted, this makes a WiMAX captive portal solution secure for most purposes. For traveling or visiting users, the EAP-TTLS solution may be complicated to use. Users need an account prior to the connection, or the visited operator needs roaming agreements with the users home operator. Roaming agreements are not common today, but is currently promoted by the WiMAX Forum. With the captive portal, users are able to buy access without having an account or subscription in advance. A captive portal solution is recommended for visiting users, and EAP-TTLS without roaming is recommended for users more permanently located in the operators area. EAP-based roaming may be deployed if roaming becomes more common in the future, but is not recommended today. In this thesis, several Mobile WiMAX access solutions are discussed, emphasizing security and user friendliness. A captive portal solution is developed, and an EAP-TTLS (Extensible Authentication Protocol - Tunneled Transport Layer Security) solution utilizing FreeRADIUS is planned. Security in WiMAX is compared to Wi-Fi very good. Even in an open WiMAX network traffic can be encrypted, this makes a WiMAX captive portal solution secure for most purposes. For traveling or visiting users, the EAP-TTLS solution may be complicated to use. Users need an account prior to the connection, or the visited operator needs roaming agreements with the users home operator. Roaming agreements are not common today, but is currently promoted by the WiMAX Forum. With the captive portal, users are able to buy access without having an account or subscription in advance. A captive portal solution is recommended for visiting users, and EAP-TTLS without roaming is recommended for users more permanently located in the operators area. EAP-based roaming may be deployed if roaming becomes more common in the future, but is not recommended today.
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Isa, Azmi Awang Md. "Enhancing location estimation accuracy in WiMAX networks." Thesis, Lancaster University, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.618335.
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Due to the ever increasing demand for new services and applications, wireless broadband communications is becoming even more popular since users have been provided with an "anywhere any time" type of service. Mobile worldwide interoperability for microwave access (WiMAX) provides mobile broadband connectivity and some essential applications, including location and positioning (L&P) for mobile users. In this thesis, we have utilised some of the features offered by WiMAX, including multiple input multiple output (MIMO) and beamforming, to improve the location estimation accuracy of location services. In a MIMO system, the number of links is increased, not only for the spatial multiplexing of data to be transmitted or received, but also for simultaneous distance measurement between a base station (BS) and a mobile station (MS). Utilising MIMO will both significantly improve the capacity and throughput of a wireless link and facilitate improvement of the location accuracy of a MS. We have proposed a geometrical approach using a multiple linear lines of position (MLLOP) technique for MIMO antenna mode configurations in WiMAX networks with range measurements from only three BSs in non-line of sight (NLOS) environments. Going beyond MIMO systems, an innovative location estimation algorithm, involving virtual BSs in MIMO systems (called VirBSs), is proposed and investigated, offering the reduction in NLOS error effects. We also explored existing beamforming features for improving accuracy of location estimation. A hybrid positioning method is proposed that utilises the time of arrival (TOA) and direction of arrival (DOA)-based beamforming in MIMO systems. More specifically, two hybrid L&P techniques are presented. The first of these hybrid techniques expands the fundamental principle of using an MLLOP scheme by utilizing multiple LOP instead of circular LOP to determine new lower and upper bounds of DOA The second proposed technique utilises only one MIMO SS, with range and angle measurements from two or more multi-paths, thus extending the virtual BS concept to enhance estimation accuracy with no extra network infrastructure required. We have shown that all the developed techniques provide L&P accuracy improvement with lower implementation complexity and are compatible with the existing WiMAX specifications.
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Tsitserov, Dmitry Vladimirovich. "Efficient video traffic distribution over WiMAX systems." Thesis, Lancaster University, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.664459.
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This thesis is dedicated to the development and practical verification of a new video traffic distribution technique for implementation in WiMAX systems. The proposed technique is applicable to M-health and video surveillance application areas and allows for better system resource optimization under the selected case study scenarios. The presented technique incorporates scalable video transmission of MPEG-originated elementary streams, a cross-layer delivery framework and the WiMAX MAC layer enhancement. Video segmentation is achieved through a separate transmission of elementary streams associated with the primitive objects contained in the original MPEG video scene. The introduced MAC entity, such as the Extended Classifier provides selective distribution of arriving packets between WiMAX QoS service connections. The choice of service classes and their quantity, con-elation between segmented video streams, general data streams and selected service connections is the main research focus of this work. The next part of this thesis deals with video broadcasting in WiMAX networks. The problem of variable reception conditions and video instability for broadcasting users is investigated here. A new broadcasting service, termed Enhanced Standard Definition video broadcasting, is proposed for better bandwidth optimization of WiMAX networks. The video distribution technique and the WiMAX delivery framework designated in support of a new broadcasting service are backward compatible with a WiMAX network reference model. NS-2 based computer simulations with the proposed innovations show the efficiency of these contributions that are analyzed by comparing the conventional and the introduced broadcasting algorithms.
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Robalo, Daniel Luís Silveira. "Planeamento, desenvolvimento e optimização de redes WiMAX." Master's thesis, Universidade da Beira Interior, 2008. http://hdl.handle.net/10400.6/3829.
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Esta dissertação aborda o planeamento de redes de banda larga IEEE 802.16. Após se
realizarem algumas considerações gerais sobre a evolução da norma, assim como as
suas principais características, são apresentados os aspectos essenciais das camadas
físicas e MAC (Medium Access Control), assim como uma análise dos parâmetros de
qualidade de serviço. Revêem-se as principais topologias de redes, as tecnologias de
antenas SISO e MIMO e abordar-se, brevemente, aspectos de segurança em redes
WiMAX.
Realizou-se o dimensionamento de redes ponto-a-ponto a 5.4 GHz, uma entre o
Hospital Sousa Martins (HSM), na Guarda, e a Faculdade de Ciências da Saúde da
Universidade da Beira Interior (FCS UBI), na Covilhã, e outra entre a FCS e o Hospital
Amato Lusitano (HAL), em Castelo Branco. Verificou-se a ausência de obstruções da
linha de vista entre a localização das diversas estações e repetidores. Recorrendo ao
modelo de Friis dimensiona-se os diversos feixes da ligação. A instalação final da
ligação entre a FCS e o HAL com o equipamento BreezeNET B100 foi precedida de um
teste de campo utilizando o equipamento BreezeNET B14.
Recorrendo aos modelos de Friis modificado e SUI, realiza-se o planeamento celular na
zona da Covilhã a 3.5 GHz, considerando a utilização do equipamento BreezeMAX
3000. Através de um teste de cobertura, na área sub-urbana da Covilhã, uma análise
exaustiva da topografia e densidade de edificações da zona de teste, conclui-se da
adequação da utilização do modelo de Friis modificado. Verifica-se que, através do
cálculo do expoente de propagação médio na área de teste, é possível disponibilizar um
modelo para a optimização do processo de planeamento celular. Para as duas zonas em
que se dividiu a área de teste, Este e Noroeste, obtiveram-se valores de 2.31 e 2.8, com
valores para o erro quadrático médio de 0.434 e 1.043, respectivamente.
Realizou-se ainda um segundo planeamento celular a 5.4 GHz, para o equipamento
BreezeACCESS VL. Apresentam-se os resultados do respectivo teste de cobertura,
assim como a análise comparativa dos resultados obtidos.This thesis addresses the planning of IEEE 802.16 broadband networks. After presenting some general considerations on the evolution of the standard, e.g., its main features, the essential aspects of the physical and MAC (Medium Access Control) layers, as well as a study of the quality of service parameters are addressed. The main network topologies, the SISO e MIMO technologies are reviewed and some brief considerations on WiMAX networks security are also addressed. A 5.4 GHz point-to-point network was designed, to guarantee the link between the Hospital Sousa Martins (HSM), at Guarda, and the Health Sciences Faculty of the University of Beira Interior (FCS UBI), at Covilhã. Another link is between the FCS and the Hospital Amato Lusitano (HAL), at Castelo Branco. The obstruction of line-ofsight between the location of the transmitter and relay stations was verified. The link budget was computed by using the Friis model. The actual installation of the link between the FCS and HAL, in Castelo Branco, with the BreezeNET B100 equipment, was preceded by a field trial with BreezeNET B14 equipment. By using the modified Friis and SUI models, and by considering the use of BreezeMAX 3000 equipment at 3.5 GHz, the cellular planning of the area of the city of Covilhã was performed. Through a field trial, in the sub-urban area of Covilhã, an exhaustive analysis of the topography and density of buildings of the trial area, the adequacy of the modified Friis model was demonstrated. By computing the average propagation exponent for the field trial area, a model for the optimization of the cellular planning process was provided. For the two areas in which the trial area was split into, East and Northwest ones, the obtained values for the propagation exponent were 2.31 and 2.8, while the values for the mean square error were 0.434 and 1.043 respectively. One second cellular planning exercise was addressed at 5.4 GHz, for the BreezeACCESS VL equipment. The results for the field trials and the comparative analysis between the experimental and theoretical results were addressed.
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Mukanyiligira, Didacienne. "Virtualization of multicast services in WiMAX networks." Doctoral thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/27360.
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Multicast service is one of the methods used to efficiently manage bandwidth when sending multimedia content. To improve bandwidth utilisation, virtualization is often invoked because of its additional features such as bandwidth sharing and support of services that require high volumes of transactional data. Currently, network providers are concerned with the bandwidth amount for efficient use of the limited wireless network capabilities and the provision of a better quality of service. The virtualization design of a multicast service framework should satisfy several objectives. For example, it should enable the interchange of service delivery between multiple networks with one shareable network infrastructure. Also, it should ensure efficient use of network resources and guarantee users' demands of Quality of Service (QoS). Thus, the design of virtualization of multicast service framework is a complex research study. Due to the bandwidth-related arguments, a strong focus has been put on technical issues that facilitate virtualization in wireless networks. A well-designed virtualized network guarantees users with the required quality service. Similarly, virtualization of multicast service is invoked to improve efficient utilisation of bandwidth in wireless networks. As wireless links prove to be unstable, packet loss is unavoidable when multicast service-oriented virtual artefacts are incorporated in wireless networks. In this thesis, a virtualized multicast framework was modelled by using Generalized Assignment Problem (GAP) methodology. Mixed Integer Linear Programing (MILP) was implemented in MATLAB to solve the GAP model. This was to optimise the allocation of multicast traffic to the appropriate virtual networks. Thus, the developed model allows users to have interchangeable services offered by multiple networks. Furthermore, Network Simulator version 3 (NS-3) was used to evaluate the performance of the virtualized multicast framework. Three applications, namely, voice over IP (VoIP), video streaming, and file download have been used to evaluate the performance of a multicast service virtualization framework in Worldwide Interoperability for Microwave Access (WiMAX) networks using NS-3. The performance evaluation was based on whether MILP is used or not used. The results of experimentation have revealed that there is good performance of virtual networks when multicast traffic is sent over one single virtual network instead of sending it over multiple virtual networks. Similarly, the results show that the bandwidth is efficiently used because the multicast traffic is not delivered through multiple virtual networks. Overall, the concepts, the investigations and the model presented in this thesis can enable mobile network providers to achieve efficient use of bandwidth and provide the necessary means to support services for QoS differentiations and guarantees. Also, the multicast service virtualization framework provides an excellent tool that can enable network providers to interchange services. The developed model can serve as a basis for further extension. Specifically, the extension of the model can boost load balancing in the flow allocation problem and activate a virtual network to deliver traffic. This may rely on the QoS policy between network providers. Therefore, the model should consider the number of users in order to guarantee improved QoS.
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Proença, Hugo Miguel Leonardo. "Evaluating WIMAX for real-time vehicular communications." Master's thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/1955.
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Mestrado em Engenharia Electrónica e TelecomunicaçõesOs acidentes rodoviários têm um impacto elevado na sociedade, quer devido às perdas humanas daí resultantes quer devido aos custos económicos associados. Este facto tem causado por todo o mundo o estudo de mecanismos que permitam aumentar a segurança rodoviária. Um exemplo disto é o investimento da Europa em vários projectos com vista a desenvolver estes mecanismos, onde a maior parte destas iniciativas consideram a possibilidade dos veículos comunicarem entre si e/ou com estações fixas, situadas junto da rodovia. A mobilidade dos veículos apresenta requisitos especiais, onde as comunicações sem-fios têm um papel crucial nestas aplicações. Contudo, os serviços de segurança rodoviária requerem alguns requisitos específicos, como largura de banda ou em termos de timeliness, que têm de ser cumpridos independentemente da tecnologia sem-fios usada. Neste trabalho é pretendido avaliar WiMAX para comunicações relacionadas com a segurança rodoviária, em que a coexistência de diferentes tipos de serviços é uma realidade, onde o uso dos mecanismos de qualidade de serviço fornecidos pelo WiMAX podem ser uma vantagem. ABSTRACT: Road accidents have a huge impact on the society, both because of the resulting human life losses and injuries as well as because of the associ- ated economic costs. This situation fostered the study of mechanisms for increasing road safety all over the world. In Europe, several projects are being funded to develop such mechanisms. Many of the approaches that are being pursued require the ability of the vehicles to communicate with each other and/or with fixed roadside equipments. Due to the mobility con- straints, wireless technologies have a crucial role in this kind of applications. However, road safety services have also specific demands, in terms of band- width and timeliness, that have to be met, independently of the wireless technology used. In this work, it is performed an evaluation of WiMAX for road safety communications, taking into consideration the coexistence of different types of service and that the use of quality of service mechanisms in this wireless technology could be an advantage.
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Yu, Yongxue. "Handover performance in the mobile WiMAX networks." [Tampa, Fla] : University of South Florida, 2009. http://purl.fcla.edu/usf/dc/et/SFE0003287.
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Liu, Wei-Jen, and 劉維仁. "WiMax NEMO ITS TESTBED." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/byjnc3.
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碩士國立東華大學
電機工程學系
95
Fast gradual progress of the network in the past several years, except offering the higher one widely frequently, offered the movement of the wireless network at the same time. WiMAX( Worldwide Interoperability for Microwave Access) Simplify,mean (interflow) It is one of the global latest wide-band wireless communication standards, offer a wireless " last one " (last mile) "And take action the terminal wide band connects the effective technological solution fetched, use 802.16 wireless transmission technology, need to pass the traditional telephone wire ( PSTN) or cable TV ( Cable) Surf the Net, can improve the traditional circuit and lay the difficult disappearance in very high-speed connection。WiMAX only one abbreviation of forum in fact seriously, there is a non-commercial organization " WiMAX Forum " on WiMAX, popularize IEEE 802.16 serial standards and relevant norms mainly, and prove and test IEEE 802.16 relevant equipment, these standards and norms include a lot of application technology than 3G relevant communication technology innovation that is used more extensively at the present stage In recent years, as internet network flourishing development and various kinds of wide bands connect newer gradual progress of fetching technology, cause so-called datacom and telecom agitate and converge for the first time, because internet network rapidly expansion of service market of adding etc., have accelerated the wide-band network of the construction and used to combine the video-information, data and pronunciation (triple play) ,Offer globality service, and make use of ADSL technology, FTTx technology to offer the high wide application frequently, the application that is attracted attention most at present is the merger of WiMAX and ITS。This thesis will describe that it is in ITS to combine 802.16d equipment and NEMO network popularized at present (the transportation system of intelligence) Have。Explain how to combine the existing commercialized equipment through the technology of SNMP BUS, offer the services of networks of wireless action。Will mention the system developed out too finally, the road surface action test result in fact。
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Lee, Bo-Wei, and 李伯偉. "WiMAX Mobile Consultative System." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/01357962303511394392.
Full textAbstract:
碩士國立高雄第一科技大學
資訊管理所
97
In recent years the campus security incident emerged one after another incessantly, in the television news page layout saw frequently the student had the community in the campus to fight, the self-injury or to injure other people and so on the calamity occurrence, these possibly came from the family uncoordinated problem perhaps cause student''s behavior deviation because of the schoolwork and the sentimental factor, it was unable in the situation which forewarned to injure others also to injure itself. The campus problem so forth occurs unceasingly in the daily life, therefore this research design develop motion psychology consultation system, provides early for student which needs to assist may express with treats at heart pressure pipeline, then cuts the campus accident''s formation rate. This system bracelet general psychology consultation service only defines in the face-to-face consultation and the traditional network consultation fence, but uses the hand-hold running gear consultation, lets the consult user to be possible with consultant anytime and anywhere to carry on the contacting consultation. This system utilizes the WiMax wireless broadband network omnipresent and the high bandwidth characteristic, and matches the GPS localization technology, achieves traces the user’s position, may further carry out the urgent relief operations, but the system design is mainly the student who aims at the Kaohsiung academy provides the service, therefore the use is consults to the student, this system may further expand in the future provides the use which the public figure consults.
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Chiu, Hsu-Feng, and 邱旭鋒. "Performance Analysis of WiMAX." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/43901478802150561037.
Full textAbstract:
碩士國立臺灣大學
資訊工程學研究所
96
IEEE 802.16 wireless metropolitan area networks have recently become an extremely popular network technique. However, within the new protocol, performance is still not broadly discussed. This research aims at the investigating of the performance and potential issues. In our study, the NIST modules upon NS2 are utilized to acquire a fair performance analysis. We investigate the ability of WiMAX with immobile users under different parameters of PHY and MAC. First, we would like to figure out how modulation affects on throughput. As modulation is becoming better, throughput is getting higher. With the best modulation 64-QAM-cc-3/4, throughput is up to 52Mbps. Second, we measure throughput with different traffic loadings. In increasing traffic loading we will get higher throughput. However, a high traffic loading will cause the bandwidth request overflowed. Thus we will get abnormal throughput. Third, we allocate different numbers of SSs in our scenario to observe the time delay. The result shows that more SSs will cause larger delay. However, packet loss has a more significant effect on influencing decrease of delay. Finally, we test the performance of different applications including Voice over IP (VoIP), video stream and data. Obviously, VoIP traffic type has the least delay. When testing the handoff function, we find that three problems exist in DSDV (Destination-Sequenced Distance-Vector Routing). The first one is concerned with the domain restriction. BSs have to be in different domains, or neighbor BSs can’t be found. The secondary issue is the path selection. Packets in MS can not find the right routing path, which will cause the failure of data transmission. In addition, using DSDV takes more than ten seconds to reconnect after handoff accomplishing. To overcome the above problems, we utilize the mobile module of NIST to support the handoff function in IEEE 802.16e. The module includes MIHF (Media Independent Handover Function) agent for performing packet delivering and ND (Neighbor Discovery) agent for neighbor discovering. Our result reveals that the handover latency is less than 50 ms even when velocity is up to 70 km/hr. This research discovers the effects on performance with different modulation, traffic loading, numbers of SSs, and applications. We also find that using DSDV in processing handoff has potential problems and could be successfully carried out by MIHF and ND agents. In summary, our experiments indicate that WiMAX indeed has superior performance on throughput and mobility. Our results could be provided as references for designing and certifying real products.
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Su, Yung-Shou, and 蘇勇守. "Wimax/RF Module Design." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/68027786500662118911.
Full textAbstract:
碩士中華大學
電機工程學系(所)
98
In recent years, the wireless communication applications have caused globally widespread attention, included personal mobile telecommunication and the wireless local area networks. OFDM is a multicarrier modulation technique for high data rate transmission. Although OFDM technique provides a lot of advantages in transmission, Suppression of high side lobes power in OFDM systems promotes the quality of the wireless transmission and enables higher spectral efficiency in the case of OFDM spectrum sharing systems . This paper is conferred about the basic theory of RF module and design technologies of circuit, especially focused on the principles, analysis and design of RF circuit, and figure how reduce size of each circuit can proceed to the trend of miniaturization. The operating frequency range of WiMAX front-end module is 2.3~2.7 GHz. Above all, the cost is the key to commercialize the wireless communication systems successfully or not, we just earned this lesson from how WiMAX set up in Taiwan.
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Hsiao, Young Choung, and 蕭永忠. "WiMAX Research and System planning." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/38195041340168709669.
Full textAbstract:
碩士國立臺灣科技大學
電子工程系
95
WiMAX system has attracted a lot of attention recently . However, the channel characterization of the WiMAX system is still little to know by most of the engineering expert the wireless commonication arena . In this thesis , we present some empirical data obtained form a WiMAX 16 e system installed in the Taipei Metropolitan area . Based on the empirical data , a model is proposed to describe the channel characteristics of the WiMAX system in the metropolitan area .
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Chuang, Chia-ning, and 莊家寧. "Multiplexer Design for WiMAX Applications." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/74217188767279720413.
Full textAbstract:
碩士國立中央大學
電機工程研究所
98
In the thesis, diplexers and triplexers for WiMAX applications are proposed. The proposed diplexer is mainly composed of a 1/2 ? and a 1/4 ? parallel-coupled-resonator bandpass filters. By using 1/4 ? parallel-coupled-resonator filter, the spurious passband will appear at 3f0. Thus, the isolation between two channels can be enhanced. In many conventional diplexer designs, T-junction is often used to connect both filters. This strategy could lead to the increase of the circuit area. Therefore, instead of the T-junction, common coupled lines are used to connect these two filters. By using the proposed matching network, a compact diplexer of high isolation (>30 dB) is thus obtained. In the triplexer dsign, the third filter is added to the diplexer mentioned above. The signal is coupled to the third filter from the top layer to the bottom layer through the slot aperture on the ground. Then, we implemented input matching network of the triplexer without increasing extra area. The measured isolations of triplexer among channels are all better than 20 dB. All circuits are fabricated y using FR-4 substrate. The relative permittivity and loss tangent of the substrate are 4.4 and 0.02, respectively. The measured results are in agreement with the simulated results.
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Lin, Kuang –Wei, and 林光韋. "WiMAX Basestation Measurement in Practice." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/34911060315507962475.
Full textAbstract:
碩士國立臺灣海洋大學
通訊與導航工程系
96
Abstract Thesis this probe into WiMAX market, relevant specification and WiMAX trader who operates network in make, open frequency band, begin relevant test jobs faced when disposing platform on the base, for example the operating trader must observe the regulation regarding wireless frequency used of the government, or conveyer power level, correct frequency regulated in the range are used etc., in case that cause interfering with to other users, guarantee the correct operation of the network equipment. The ones that must all meet the responsible institution to take frequency at the same time in these are used correctly, and certainly have service quality offered toward general user. Research until base station faced soon install and link, transport, test, do discussion to WiMAX trader who operates network purpose of this text, For example WiMAX spectral energy changes, energy to the change of time, and is learnt Preamble Power as the greatest influence energy by it, In addition we are examined the adjoin power ratio of channel by quantity to judge platform on the base to the interference characteristic near the pass way, and make use of smooth degree of standards of the frequency spectrum that WiMAX forum proposes to judge the efficiency of an amplifier of the base, Understand adjusting the quality of changing of the signal by the analysis of the constellation picture finally. We are besides utilizing WiMAX forum relevant regulations in course, the standard relative standard that we consult 3GPP TS25.141 and 802.16 Broadband wireless access working group that the forum has not been mentioned will come Result that the judging amount examines, A persons who can offer relevant family property consult as actually affair. Key world: WiMAX(Worldwide Interoperability for Microwave Access)
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Tsai, Shen-Chiuan, and 蔡聖權. "WiMAX antenna design for notebook." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/74739717420669260708.
Full textAbstract:
碩士國立中央大學
通訊工程研究所碩士在職專班
97
The purpose of this thesis is to design a WiMAX antenna that is more suitable for notebook. From the beginning of antenna classification and WiMAX brief to actually antenna design, then analyze the antenna characteristic of our design and compare those characteristic with other design. Finally, we can find out the characteristic of our design is not only conform to the standard that we define at beginning, the location of antenna is also more close to actually application. With another advantage, the area of the antenna is reduce almost 30 % and does not affect any other characteristic of antenna. This is increasing the application region more and more.
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Shen, Guan-Yin, and 沈冠穎. "CPW-FED WiMAX/WLAN ANTENNAS." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/69463982720163812966.
Full textAbstract:
碩士大同大學
通訊工程研究所
97
In this thesis, two unique approaches are respectively applied to design a CPW-fed circularly and a linearly polarized antenna. For the circularly polarized antenna, center conductor of the CPW is bended into a semi-circular shape and two ground branches of the CPW are connected together to form an open-aperture. We may consider that center conductor of the CPW is modified to form the first type and is protruded into the aperture. By keeping this aperture, the center conductor of the CPW can be modified into the second type. The second type results in the linearly polarized antenna by extending and widening the width of the center conductor of the CPW. The CP antenna is designed and implemented for WLAN standards of 2.4 GHz and WiMAX standard of 2.5 GHz (2.5-2.69GHz). The measured 10-dB return loss bandwidth is 22.04 %( 2.22-2.77GHz), the 3dB axial ratio is 17.4% (2.35-2.8GHz), and the in-band antenna gain lies between 1~4.5 dBic. The LP antenna is designed to cover 2.5/3.5/5.5 GHz of WiMAX bands and 5.8 GHz of WLAN bands. The measured 10-dB return loss bandwidth is 44.6% (2.42-3.81GHz) and 16.33% (5.38-6.351GHz), and the in-band antenna gain is around 0.15~4.4 dBi. The latter one may further improve the reception ability.
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Yang, Chih-Hao, and 楊志豪. "WiMAX and HSDPA Interworking Mechanism." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/28405408995588668196.
Full textAbstract:
碩士國立臺灣科技大學
電子工程系
96
This thesis presented a set of comprehensive interworking mechanisms between WiMAX (World Interoperability for Microwave Access) and HSDPA (High Speed Downlink Packet Access) to fulfill the integration and development of latest wireless broadband data service. The proposed interworking mechanisms comprise: WiMAX-HSDPA interworking architecture, QoS (Quality of Service) guarantee mechanism, as well as handover trigger module (HTM). This thesis first introduced an interworking architecture which complied with both HSDPA and WiMAX standards. Based on this architecture, we recommended a QoS guarantee mechanism i.e. “WiMAX-HSDPA service aware QoS mapping” (WHSAQM) to assure the QoS continuity between these two networks during handover. Furthermore, the HTM which consists of network connection management, pre-registration, signal monitoring and handover trigger mechanisms support to reply the network and radio channel status promptly to minimize the potential service degradation and handover interruption. Eventually, field tests are performed to verify the key performance indicators (KPIs) of services and the feasibility of the recommended mechanisms. After verification in the field test, all the services can be seamlessly handover between these two networks, and the QoS requirement of services can be guaranteed. While the WiMAX spectrum had just been released by some countries, this thesis provides a feasible interworking solution for those existing cellular operators or green-field operators who have plans to implement the WiMAX and HSDPA in the future.
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Yang, Gilbert, and 楊繼斌. "Seeing What’s Next on WiMAX." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/61325390904286839599.
Full textAbstract:
碩士國立交通大學
管理學院碩士在職專班經營管理組
94
WiMAX (Worldwide Interoperability for Microwave Access) continuously draw much attention from telecommunications industry and considered a viable solution for end-user’s all telecommunications needs. This reminds us what 3G（Third Generation） wireless had been treated at very beginning and have done so far. The industry probably needs a better way to evaluate new technology and its application. This research is based on the viewpoint of disruptive innovation theory to locate the key success factors, and inspect WiMAX technology and services, evaluate their viability, and derive possible strategies for challengers. The key findings from this paper include: WiMAX conforms to the conditions of disruptive innovation theory, even though challengers need appropriate strategies to catch market share, and the recommended likely strategies for challengers are given.
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Liou, Jheng-You, and 劉政佑. "Simulink platform of WiMAX system." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/37121545100232310503.
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Chin, Marta Chan. "Integração do Wimax no IMS." Master's thesis, 2008. http://hdl.handle.net/10071/2542.
Full textAbstract:
Hoje em dia as redes de telecomunicações oferecem cada vez mais serviços baseados na tecnologia IP. Para se destacarem no mercado e aumentarem as suas receitas, os operadores sentem a necessidade de desenvolver e distribuir novas aplicações o mais simples e rápido possível. Face a esta necessidade, o IMS surge como uma possível solução, uma vez que define um ambiente ideal para a criação e desenvolvimento destes novos serviços, de um modo standard e independente do tipo de acesso.
As vantagens que o IMS proporciona ao desenvolvimento e distribuição de serviços, combinada com uma tecnologia de acesso banda larga wireless, como o Wimax, que oferece maior cobertura e maiores velocidades de transmissão, formam uma solução de banda larga unificada que combina duas tecnologias de implementação aberta, que permitem a convergência entre redes e o fornecimento de múltiplos serviços cada vez mais inovadores.
Nesta tese serão abordados e discutidos os possíveis cenários de integração entre a tecnologia Wimax e a rede IMS.Today, telecommunications networks offer more services based on IP technology. In order to take the lead in the market and increase their revenue, operators feel the need to develop and distribute new applications as simple and quick as possible. Against this need, the IMS is emerging as a possible solution, since it defines an ideal environment for creation and development of these new services, in a standard way and independent of the type of network access used. The benefits that IMS provides to the development and distribution services, combined with a broadband wireless access technology such as Wimax, which offers greater coverage and higher transmission speeds, form a unified broadband solution that combines two technologies of open standards, enabling the convergence of networks and the provision of multiple services increasingly innovative. This dissertation will address and discuss the possible scenarios of integration between the Wimax technology and the IMS network.
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Lau, Hsien-Wen, and 劉獻文. "WiMAX 5.8GHz Transceiver RF Module." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/82353836479969534753.
Full textAbstract:
碩士國立交通大學
電信工程系所
96
The proposed WiMAX 5.8GHz Transceiver RF Module is fabricated with 6-layer FR4 printed circuit board. The architecture is mainly following the TI’s RFIC. System architecture belongs to TDD. Originally, two kinds of architecture are considered. For cost-down consideration, one of them is adopted. After finishing of circuit schematic block diagram, layout, and fabrication, the measured TX output power attains -6dBm, the RX gain control range is from 5dB to 60dB, and OP1dB is -7.83dBm.
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Lin, Yung-Chun, and 林湧鈞. "Enhancing Mobility Management for WiMAX." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/16229671529251136679.
Full textAbstract:
博士國立交通大學
資訊科學與工程研究所
98
As mobile subscriber population rapidly grows, mobile access for broadband services becomes an important part of human life. IEEE 802.16e mobile Worldwide Interoperability for Microwave Access (WiMAX) provides broadband wireless services with wide service coverage, high data throughput, and high mobility. In WiMAX, mobility management (i.e., location management and handoff management) is one of the most important issues to support mobile services. Location management function tracks the roaming Mobile Stations (MSs) for service delivery, and handoff management function maintains service continuity during MS mobility. Such functions are important for mobile telephony services, including conference/video call and Push to Talk over Cellular (PoC). In this dissertation, we investigate the mobility management issues for WiMAX networks. For location management, we first propose an analytic model to study the Location Update (LU) performance with overlapping Location Area (LA) configuration. Our study indicates how to determine the appropriate overlap among LAs. Then we investigate the performance for WiMAX LU procedure with Anchor Paging Controller (APC) relocation. In WiMAX, an APC is assigned to an MS to handle its location tracking and can be dynamically relocated during the LU procedure. By the analytic results, we provide guidelines to utilize the APC relocation for MSs with various moving behaviors. For handoff management, to support service continuity for high mobility MSs, we proposed the Repacking on Demand (RoD) for the Hierarchical WiMAX Network (HWN) by considering the MS moving speeds. Our study quantitatively indicates that RoD is less sensitive to MS speeds and outperforms the other previous proposed schemes significantly. The research results presented in this dissertation provide some useful mechanisms and guidelines for WiMAX operators to achieve high system performance in their networks.
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Chuang, Shao Chun, and 莊紹群. "Implementation of WiMAX portable router." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/99625044401988983833.
Full textAbstract:
碩士國立臺北大學
通訊工程研究所
98
Wireless communication has changed the way people communicate. How to provide broadband wireless is always a great challenge in limited frequency resources.WiMax and LTE seems to be the solution in the next decade. According to WiMAX Forum, as of May 2009, 475 networks are deployed in 140 countries. However, very few of the mobile devices and laptops have integrated with WiMAX access capability. It is a very big challenge for operators to have current users easily accessing the internet through WiMAX without selling new devices which have WiMAX capability to them. The idea of portable hotspot using WiMAX might be the easiest and most attractive way for most of users. In this thesis we have implemented a portable internet access device with low power consumption. This device has routing capability to access WiMAX and can be connected by all mobile devices with Wi-Fi or internet capability. This device is driven by battery such that it is portable.
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Wu, Chung-Hsi, and 吳崇熙. "Implementation of WiMAX Baseband Generator." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/5pp483.
Full textAbstract:
碩士國立臺北科技大學
資訊工程系研究所
97
This topic is based on IEEE 802.16e-2005 communication protocol, expect to implement the low cost WiMAX baseband (or intermediate frequency) generator, it can generate WiMAX frame that accords with standard, and can develop as one platform of simulation and research for WiMAX. In order to meet the demands of bandwidth transfer and throughput for wireless system, there must be enough ability in the basic hardware platform. In hardware, we adopt the TI’s TMS320DM6446 DSP chip, FPGA module, DAC module and the circuit board make by ourself for connection. DSP has the high ability of computation, and offers the good development environment. FPGA has highly flexible and disposition, because the standard is changing constantly too, make this platform more elastic through the combination of DSP and FPGA.
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Liu, Tsai-Hwa, and 劉才華. "A Beneficial Analysis for WiMAX Operators to Migrate Their Network from WiMAX to TD-LTE." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/3v3y4a.
Full textAbstract:
碩士國立交通大學
管理學院高階主管管理碩士學程
101
The main purposes of this study aim to explore the evolution of broadband wireless communication network, and the global trends of response by telecom service providers. Then to find the possible strategies of Taiwan WiMAX operators for the future. To come out the total solution of migrating from WiMAX to TD-LTE network, this study focuses on four important aspects including technology, eco-system, market, and policy &; regulation. The analysis on 4G mobile broadband communication eco-system is also used to identify the pros and cons of WiMAX and TD-LTE networks. Furthermore, this study to estimate the TCO (CAPEX and OPEX), and future profit from the migration for WiMAX operator based on current global market and policy of available 4G spectrums. The research method of this study is to perform in-depth interview with domain experts from the areas of industry, research, and academia. The scenario analysis method was applied to conclude the best solutions for WiMAX operators in Taiwan. According to the result, the WiMAX operators should migrate from WiMAX to TD-LTE network in order to survive in next generation 4G telecom market. We strongly suggest, the WiMAX operators may cooperate with the university research groups to speed up and lower the cost of migration. The research teams also can help WiMAX operators to develop more application services to improve the competence for the fast-changing telecom market.
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Huang, Shuo-Chao, and 黃碩超. "A Four-Sector Switchable WiMAX Antenna." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/u6x253.
Full textAbstract:
碩士國立中山大學
電機工程學系研究所
96
A four-sector switchable WiMAX antenna, for indoor use in the 4.9 -5.0 GHz frequency bands, is presented. The prototype antenna is designed to provide a higher gain in a specified sector region. Furthermore, the radiation beam is electronically steerable to provide space diversity in four different sectors. Each sector of this antenna includes an array of two rectangular microstrip patches. The air gap between the bottom substrate of microstrip patches and the ground plane is increased to 3 mm, which can aid in accomplishing a high-gain and wideband design goal. A solid-state microwave switch is used to select one of the four sectors.
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Tze-Huei, Kao. "Low Voltage Analog Baseband for WiMAX." 2006. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-2507200621021500.
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Ahmad, Mohammad Hamidullah. "QoS Scheduling in IEEE802.16/WiMAX Networks." Thesis, 2011. http://spectrum.library.concordia.ca/35793/1/Ahmad_MSc_F2011.pdf.
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Albluwi, QUTAIBA. "Frame Partitioning in WiMax Mesh Mode." Thesis, 2008. http://hdl.handle.net/1974/1543.
Full textAbstract:
WiMax or the IEEE 802.16 standard is one of the most promising broadband wireless
technologies nowadays. It is characterized by its high data rates, large coverage area,
flexible design and QoS support. The standard defines two modes of operation: Point-to-
Multi-Point (PMP) and the Mesh Mode. In the first mode, all nodes are connected
directly to the base station and communication is not allowed amongst nodes. In the mesh mode, nodes are placed in an ad hoc manner communicating to neighbors and relaying the traffic of other nodes. The goal of this thesis is to design a partitioning scheme for the frame structure of the Mesh mode. Increasing the frame utilization would
result in better support for QoS applications and optimized resource allocation, and
thus revenue increase from the service provider’s perspective.
The mesh frame is divided into control and data, which are further divided into
centralized and distributed portions. We propose a novel and efficient scheme for partitioning the data subframe between the two schedulers. We use a Markovian model
that studies the system behavior in the long run, and provides predictions based on
analysis of previous window of frames. We further enhance the decision by tuning the
partitioning through statistical analysis of smaller windows to accommodate demand
changes. Our simulations show that the proposed scheme achieves high utilization
under different network and traffic conditions and decreases the packet overflow.Thesis (Master, Computing) -- Queen's University, 2008-10-02 18:41:36.551