61 research outputs found
Fourth Generation Wireless Systems: Requirements and Challenges for the Next Frontier
Fourth generation wireless systems (4G) are likely to reach the consumer market in another 4-5 years. 4G comes with the promise of increased bandwidth, higher speeds, greater interoperability across communication protocols, and user friendly, innovative, and secure applications. In this article, I list the requirements of the 4G systems by considering the needs of the users in the future. These requirements can be met if technical and business challenges can be overcome. Technical challenges include mobility management, quality of service, interoperability, high data rate, security, survivability, spectrum, intelligent mobile devices, middleware, and network access. I discuss the most plausible solutions to these technical challenges in this paper. Business-related challenges include billing, payment methods, pricing, size of investments, content provision and mediation, and the trade-off between richness and reach. If these technical and business challenges can be met, then 4G will become the next frontier in data and voice communication infrastructure
Recent Advances in Wireless Communications and Networks
This book focuses on the current hottest issues from the lowest layers to the upper layers of wireless communication networks and provides "real-time" research progress on these issues. The authors have made every effort to systematically organize the information on these topics to make it easily accessible to readers of any level. This book also maintains the balance between current research results and their theoretical support. In this book, a variety of novel techniques in wireless communications and networks are investigated. The authors attempt to present these topics in detail. Insightful and reader-friendly descriptions are presented to nourish readers of any level, from practicing and knowledgeable communication engineers to beginning or professional researchers. All interested readers can easily find noteworthy materials in much greater detail than in previous publications and in the references cited in these chapters
A Review of Service Quality in Integrated Networking System at the Hospital Scenarios
Hospital networking system is progressing into a more unified method by connecting technology that utilizes wireless networking technologies into backbone networks. Even though multiple joined circumstances have been acknowledged in the published articles, a common medical facility has not been thoroughly studied and continued to be a difficult subject that is pending. The main challenge faced by networking consultants is the smooth unification of all the components in an all-in-one of healthcare delivery system. A perfect understanding of the functions of the unified networking is essential for effective designing and utilization of such knowledge in the medical backgrounds. This paper denotes the design and review of unified networking system circumstances in a hospital background. The effect of the types of traffic for example the audio and visual, system loads, size and strength of the network line is studied by a test run. Three pilot test studies have been conducted in radiology A&E and ICU conditions. Each condition shows the requirements for a particular type of traffic which then becomes the definite system behaviour. In the case of a radiology requirement, email and FTP traffic are noted to function effectively within the regular-to-big networking systems. In an A&E situation, VoIP circulations create very little jitters and missing data; it is linked with the prerequisites of QoS. In ICU situations, the video conferencing function downgrades the size of the network. Therefore, a QoS enabled gadget is suggested to minimise the packet delay and data losses. This study gives an overall explanation of wireless telemedicine technology and QoS. The findings of this study are summarised and arranged. Besides, the quality of service which has to be studied through the wireless telemedicine technology has been indicated. The findings of this study will provide a useful perspective in the investigation of QoS in wireless telemedicine technology and serve as a foundation for any individuals who are intrigued in the research of âwireless telemedicine technology for e-healthcare service
Acesso banda larga sem fios em ambientes heterogéneos de próxima geração
Doutoramento em Engenharia InformĂĄticaO acesso ubĂquo Ă Internet Ă© um dos principais desafios para os operadores
de telecomunicaçÔes na prĂłxima dĂ©cada. O nĂșmero de utilizadores da Internet
estĂĄ a crescer exponencialmente e o paradigma de acesso "always connected,
anytime, anywhere" Ă© um requisito fundamental para as redes mĂłveis de
próxima geração. A tecnologia WiMAX, juntamente com o LTE, foi
recentemente reconhecida pelo ITU como uma das tecnologias de acesso
compatĂveis com os requisitos do 4G. Ainda assim, esta tecnologia de acesso
não estå completamente preparada para ambientes de próxima geração,
principalmente devido à falta de mecanismos de cross-layer para integração de
QoS e mobilidade. Adicionalmente, para além das tecnologias WiMAX e LTE,
as tecnologias de acesso rĂĄdio UMTS/HSPA e Wi-Fi continuarĂŁo a ter um
impacto significativo nas comunicaçÔes móveis durante os próximos anos.
Deste modo, Ă© fundamental garantir a coexistĂȘncia das vĂĄrias tecnologias de
acesso rĂĄdio em termos de QoS e mobilidade, permitindo assim a entrega de
serviços multimédia de tempo real em redes móveis.
Para garantir a entrega de serviços multimédia a utilizadores WiMAX, esta
Tese propÔe um gestor cross-layer WiMAX integrado com uma arquitectura de
QoS fim-a-fim. A arquitectura apresentada permite o controlo de QoS e a
comunicação bidireccional entre o sistema WiMAX e as entidades das
camadas superiores. Para além disso, o gestor de cross-layer proposto é
estendido com eventos e comandos genéricos e independentes da tecnologia
para optimizar os procedimentos de mobilidade em ambientes WiMAX. Foram
realizados testes para avaliar o desempenho dos procedimentos de QoS e
mobilidade da arquitectura WiMAX definida, demonstrando que esta Ă©
perfeitamente capaz de entregar serviços de tempo real sem introduzir custos
excessivos na rede.
No seguimento das extensÔes de QoS e mobilidade apresentadas para a
tecnologia WiMAX, o Ăąmbito desta Tese foi alargado para ambientes de
acesso sem-fios heterogéneos. Neste sentido, é proposta uma arquitectura de
mobilidade transparente com suporte de QoS para redes de acesso multitecnologia.
A arquitectura apresentada integra uma versĂŁo estendida do IEEE
802.21 com suporte de QoS, bem como um gestor de mobilidade avançado
integrado com os protocolos de gestĂŁo de mobilidade do nĂvel IP. Finalmente,
para completar o trabalho desenvolvido no Ăąmbito desta Tese, Ă© proposta uma
extensĂŁo aos procedimentos de decisĂŁo de mobilidade em ambientes
heterogéneos para incorporar a informação de contexto da rede e do terminal.
Para validar e avaliar as optimizaçÔes propostas, foram desenvolvidos testes
de desempenho num demonstrador inter-tecnologia, composta pelas redes de
acesso WiMAX, Wi-Fi e UMTS/HSPA.Ubiquitous Internet access is one of the main challenges for the
telecommunications industry in the next decade. The number of users
accessing the Internet is growing exponentially and the network access
paradigm of âalways connected, anytime, anywhereâ is a central requirement
for the so-called Next Generation Mobile Networks (NGMN). WiMAX, together
with LTE, was recently recognized by ITU as one of the compliant access
technologies for 4G. Nevertheless, WiMAX is not yet fully prepared for next
generation environments, mainly due to the lack of QoS and mobility crosslayer
procedures to support real-time multimedia services delivery.
Furthermore, besides the 4G compliant WiMAX and LTE radio access
technologies, UMTS/HSPA and Wi-Fi will also have a significant impact in the
mobile communications during the next years. Therefore, it is fundamental to
ensure the coexistence of multiple radio access technologies in what QoS and
mobility procedures are concerned, thereby allowing the delivery of real-time
services in mobile networks.
In order to provide the WiMAX mobile users with the demanded multimedia
services, it is proposed in this Thesis a WiMAX cross-layer manager integrated
in an end-to-end all-IP QoS enabled architecture. The presented framework
enables the QoS control and bidirectional communication between WiMAX and
the upper layer network entities. Furthermore, the proposed cross-layer
framework is extended with media independent events and commands to
optimize the mobility procedures in WiMAX environments. Tests were made to
evaluate the QoS and mobility performance of the defined architecture,
demonstrating that it is perfectly capable of handling and supporting real time
services without introducing an excessive cost in the network.
Following the QoS and mobility extensions provided for WiMAX, the scope of
this Thesis is broaden and a seamless mobility architecture with QoS support in
heterogeneous wireless access environments is proposed. The presented
architecture integrates an extended version of the IEEE 802.21 framework with
QoS support, as well as an advanced mobility manager integrated with the IP
level mobility management protocols. Finally, to complete the work within the
framework of this Thesis, it is proposed an extension to the handover decisionmaking
processes in heterogeneous access environments through the
integration of context information from both the network entities and the enduser.
Performance tests were developed in a real testbed to validate the
proposed optimizations in an inter-technology handover scenario involving
WiMAX, Wi-Fi and UMTS/HSPA
Recommended from our members
Application priority framework for fixed mobile converged communication networks
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.The current prospects in wired and wireless access networks, it is becoming increasingly important to address potential convergence in order to offer integrated broadband services. These systems will need to offer higher data transmission capacities and long battery life, which is the catalyst for an everincreasing variety of air interface technologies targeting local area to wide area connectivity. Current integrated industrial networks do not offer application aware context delivery and enhanced services for optimised networks. Application aware services provide value-added functionality to business applications by capturing, integrating, and consolidating intelligence about users and their endpoint devices from various points in the network. This thesis mainly intends to resolve the issues related to ubiquitous application aware service, fair allocation of radio access, reduced energy consumption and improved capacity. A technique that measures and evaluates the data rate demand to reduce application response time and queuing delay for multi radio interfaces is proposed. The technique overcomes the challenges of network integration, requiring no user intervention, saving battery life and selecting the radio access connection for the application requested by the end user. This study is split in two parts. The first contribution identifies some constraints of the services towards the application layer in terms of e.g. data rate and signal strength. The objectives are achieved by application controlled handover (ACH) mechanism in order to maintain acceptable data rate for real-time application services. It also looks into the impact of the radio link on the application and identifies elements and parameters like wireless link quality and handover that will influence the application type. It also identifies some enhanced traditional mechanisms such as distance controlled multihop and mesh topology required in order to support energy efficient multimedia applications. The second contribution unfolds an intelligent application priority assignment mechanism (IAPAM) for medical applications using wireless sensor networks. IAPAM proposes and evaluates a technique based on prioritising multiple virtual queues for the critical nature of medical data to improve instant transmission. Various mobility patterns (directed, controlled and random waypoint) has been investigated and compared by simulating IAPAM enabled mobile BWSN. The following topics have been studied, modelled, simulated and discussed in this thesis: 1. Application Controlled Handover (ACH) for multi radios over fibre 2. Power Controlled Scheme for mesh multi radios over fibre using ACH 3. IAPAM for Biomedical Wireless Sensor Networks (BWSN) and impact of mobility over IAPAM enabled BWSN. Extensive simulation studies are performed to analyze and to evaluate the proposed techniques. Simulation results demonstrate significant improvements in multi radios over fibre performance in terms of application response delay and power consumption by upto 75% and 15 % respectively, reduction in traffic loss by upto 53% and reduction in delay for real time application by more than 25% in some cases
Integrating Context-Awareness in the IP Multimedia Subsystem for Enhanced Session Control and Service Provisioning Capabilities
The 3GPP-defined IP Multimedia Subsystem (IMS) is becoming the de-facto standard for IP-based multimedia communication services. It consists of an overlay control and service layer that is deployed on top of IP-based mobile and fixed networks. This layer encompasses a set of common functions (e.g. session control functions allowing the initiation/modification/termination of sessions) and service logics that are needed for the seamless provisioning of IP multimedia services to users, via different access technologies. As it continues to evolve, the IMS still faces several challenges including: the enabling of innovative and personalized services that would appeal to users and increase network operators' revenues; its interaction with other types of networks (e.g. wireless sensor networks) as means to enhance its capabilities; and the support of advanced QoS schemes that would manage the network resources in an efficient and adaptive manner. The context-awareness concept, which comes from the pervasive computing field, signifies the ability to use situational information (or context) in support to operations and decision making and for the provision of relevant services to the user. Context-awareness is considered to enhance users' experience and is seen as an enabler to adaptability and service personalization - two capabilities that could play important roles in telecommunication environments. This thesis focuses on the introduction of the context-awareness technology in the IMS, as means to enhance its session control and service provisioning capabilities. It starts by presenting the necessary background information, followed by a derivation of requirements and a review of the related work. To ensure the availability of contextual information within the network, we then propose an architecture for context information acquisition and management in the IMS. This architecture leverages and extends the 3GPP presence framework. Building on the capabilities of this architecture, we demonstrate how the managed information could be integrated in IMS operations, at the control and service levels. Showcasing control level integration, we propose a novel context-aware call differentiation framework as means to offer enhanced QoS support (for sessions/calls) in IMS-based networks. This framework enables the differentiation between different categories of calls at the IMS session control level, via dynamic and adaptive resource allocation, in addition to supporting a specialized charging model. Furthermore, we also propose a framework for enhanced IMS emergency communication services. This framework addresses the limitations of existing IP-based emergency solutions, by offering three main improvements: a QoS-enhanced emergency service; a context-aware personalized emergency service; and a conferencing-enhanced emergency service. We demonstrate the use of context awareness at the IMS service level using two new context-aware IMS applications. Finally, to validate our solutions and evaluate their performance, we build various proof-of-concept prototypes and OPNET simulation model
Radio Communications
In the last decades the restless evolution of information and communication technologies (ICT) brought to a deep transformation of our habits. The growth of the Internet and the advances in hardware and software implementations modiïŹed our way to communicate and to share information. In this book, an overview of the major issues faced today by researchers in the ïŹeld of radio communications is given through 35 high quality chapters written by specialists working in universities and research centers all over the world. Various aspects will be deeply discussed: channel modeling, beamforming, multiple antennas, cooperative networks, opportunistic scheduling, advanced admission control, handover management, systems performance assessment, routing issues in mobility conditions, localization, web security. Advanced techniques for the radio resource management will be discussed both in single and multiple radio technologies; either in infrastructure, mesh or ad hoc networks
Telecommunications Networks
This book guides readers through the basics of rapidly emerging networks to more advanced concepts and future expectations of Telecommunications Networks. It identifies and examines the most pressing research issues in Telecommunications and it contains chapters written by leading researchers, academics and industry professionals. Telecommunications Networks - Current Status and Future Trends covers surveys of recent publications that investigate key areas of interest such as: IMS, eTOM, 3G/4G, optimization problems, modeling, simulation, quality of service, etc. This book, that is suitable for both PhD and master students, is organized into six sections: New Generation Networks, Quality of Services, Sensor Networks, Telecommunications, Traffic Engineering and Routing
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