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Wireless Communications, IEEE

Issue 3 • Date June 2009

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Displaying Results 1 - 15 of 15
  • Front cover - IEEE Wireless Communications

    Page(s): c1
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    Freely Available from IEEE
  • Table of contents

    Page(s): 1
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    Freely Available from IEEE
  • Applications and support technologies: bettering our living environments [Editor's Note]

    Page(s): 2 - 3
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    Freely Available from IEEE
  • Sharing government spectrum with private users: opportunities and challenges

    Page(s): 4 - 5
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (921 KB) |  | HTML iconHTML  

    Measurements of spectrum occupancy typically confirm the expectation that spectrum assigned to government entities often has low average utilization in urban areas despite its potential for peaks during emergencies. By contrast, spectrum assigned to the private sector is usually most heavily used in urban areas. The second generation of government spectrum sharing started in 2004 with cognitive-radio-based sharing of the 5.25-5.35 and 5.47-5.725 GHz radar bands by unlicensed Wi-Fi-like systems. This sharing is called dynamic frequency selection (DFS) in regulatory and standards publications. Although DFS enabled sharing, the technical criteria were very conservative due to the fact that the military radar systems were not designed for sharing and the fact that interference to these radar systems had to be kept to a negligible likelihood. View full abstract»

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  • Applications and support technologies for mobility and enterprise services [Guest Editorial]

    Page(s): 6 - 7
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    Freely Available from IEEE
  • Business communications standardization in ETSI

    Page(s): 8 - 14
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (210 KB) |  | HTML iconHTML  

    Enterprise networks are in the process of a major and rapid evolution toward IP. At the same time, the 3GPP IP multimedia subsystem is gaining momentum in the telecom industry as the target architecture for delivering and controlling multimedia services in carrier-grade IPbased networks. As a logical consequence, standards are emerging that enable the support of business trunking and hosted enterprise services using the IMS. This article provides insight into the benefits of this approach and takes an in-depth look at related ETSI standards. View full abstract»

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  • IMS-based presence service with enhanced scalability and guaranteed QoS for interdomain enterprise mobility

    Page(s): 16 - 23
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (279 KB) |  | HTML iconHTML  

    Enterprise mobility and IP multimedia system corporate services are becoming more relevant; in particular, the IMS-based presence service is starting to provide different kinds of seamlessly mobile services, with context awareness in a wide range of enterprise-deployment scenarios. However, the deployment of presence-based enterprise services in wide and heterogeneous wireless networks still faces several challenges. First of all, scalability and differentiated quality are considered crucial, especially under heavy traffic conditions and when dealing with inter-domain mobility scenarios. This article presents an overview of very recent research contributions about the standard IMS presence service and some novel proposals for scalability and quality optimization. In addition, we propose a novel presence service solution that presents three original extensions for scalability and quality: a federated model to optimize inter-domain distribution of notification messages through locality-based aggregation, a proposal for differentiated quality levels, and an extension of client-side buffering for reliable delivery of presence messages, even during user roaming. The prototype of the enhanced presence service has been deployed and validated by obtaining performance results of improved scalability in terms of CPU and memory usage in infrastructure nodes and message traffic. The prototype is openly available to the IMS community for possible refinement and extension. View full abstract»

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  • Enabling secure service discovery in mobile healthcare enterprise networks

    Page(s): 24 - 32
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (906 KB) |  | HTML iconHTML  

    Advances in wireless networks, sensors, and portable devices offer unique chances to deliver novel anytime anywhere medical services and information, thus enabling a wide range of healthcare applications, from mobile telemedicine to remote patient monitoring, from location-based medical services to emergency response. Mobile e-health has great potential to extend enterprise hospital services beyond traditional boundaries, but faces many organizational and technological challenges. In pervasive healthcare environments, characterized by user/service mobility, device heterogeneity, and wide deployment scale, a crucial issue is to discover available healthcare services taking into account the dynamic operational and environmental context of patient-healthcare operator interactions. In particular, novel discovery solutions should support interoperability in healthcare service descriptions and ensure security during the discovery process by making services discoverable by authorized users only. This article proposes a semantic-based secure discovery framework for mobile healthcare enterprise networks that exploits semantic metadata (profiles and policies) to allow flexible and secure service search/retrieval. As a key feature, our approach integrates access control functionalities within the discovery framework to provide users with filtered views on available services based on service access requirements and user security credentials. View full abstract»

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  • Mobile social networks as quality of life technology for people with severe mental illness

    Page(s): 34 - 40
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2653 KB) |  | HTML iconHTML  

    Currently, assistive technology focuses on promoting greater independence for people with disabilities by enabling them to perform tasks on a personal basis. For certain disabilities, such as cognitive impairment, the requirements for dual interface development must address the needs of target users, as well as their caregivers. Assistive technology that leverages networks of caregivers, who are nomadic or remain on the go constantly, has not been developed into useful services or even explored systematically. In this article, first we propose a general architecture of mobile social networks where individuals in the networks form a virtual community, conversing and connecting with one another, based on mobile communication. Second, we describe an implementation of mobile social networks in collaboration with a supported employment program established for people with severe mental illness. View full abstract»

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  • Service-oriented operating systems: future workspaces

    Page(s): 42 - 50
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (524 KB) |  | HTML iconHTML  

    Most people use more than one computing system for their daily work: an office computer, a corporate laptop for travel, and a private desktop computer. These machines not only differ in their power and resources but also in their environment, including deployed applications, available files, and so on. The current trend is leading to an even greater number of devices and a wider range of capabilities. This presents a major challenge to enabling the vision of the mobile user and worker. This article shows how developments in the area of service-oriented computing, embedded devices, and networking enable user-specific virtual working and private environments on the basis of new approaches toward distributed operating systems. These service-oriented operating systems extend the limited capabilities of local devices with (remote) resource pools, aimed at provisioning identical (or similar) environments in any context and location. As we explain, henceforth, future employee workspaces will concentrate much more on mobility, while the actual resources (computational power, storage, data) will be maintained through dedicated corporate server farms, thus greatly reducing the administration effort and enhancing the user experience. View full abstract»

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  • The design and implementation of an ad hoc network of mobile devices using the LIME II tuple-space framework

    Page(s): 52 - 59
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (444 KB) |  | HTML iconHTML  

    This article describes the design and implementation of a mobile ad hoc network on top of the LIME tuple-space framework and using pocket PC devices. The developed system offers capabilities that enable mobile devices to collaborate by communicating and sharing data. Using the LIME framework, neighboring mobile devices cooperate to transfer information to distant devices. Several experiments were run to evaluate the system; these showed reasonable performance in terms of the time spent to join the network, the time spent to move a message from source to destination, and the energy consumed by the device due to running the system. View full abstract»

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  • QoS-aware adaptation for satellite multimedia broadcasting via hierarchical packet scheduling

    Page(s): 60 - 68
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (382 KB) |  | HTML iconHTML  

    With the unique broadcast nature and ubiquitous coverage of satellite networks, the synergy between satellite and terrestrial networks provides opportunities for delivering wideband services to a wide range of audiences over extensive geographical areas. This article concerns the optimization techniques pertinent to packet scheduling to facilitate multimedia content delivery over the satellite with a return channel via a terrestrial network. We propose a novel hierarchical packet scheduling scheme that allocates the resources at different parts of the network in response to network dynamics and link variations while under the system power/resource constraints. Simulations prove that the HPS scheme can effectively improve the end-to-end performance and resource utilization with desirable scalability and fairness features. View full abstract»

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  • Header compressed VoIP in IEEE 802.11

    Page(s): 69 - 75
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (232 KB) |  | HTML iconHTML  

    Header compression techniques such as robust header compression can be used to reduce the overhead of IP-based traffic. Voice over IP may replace voice circuits in the next generations of wireless networks, and it is the type of traffic that benefits most from header compression because its packets have small payloads. IEEE 802.11 is a technology that will play an important role in the next generations of wireless networks. The study reported in this article shows that the maximum gain of the RoHC's U-mode when applied to VoIP over IEEE 802.11 is about 23 percent for medium or better voice quality. Values for the RoHC U-mode parameters over IEEE 802.11 are also suggested. View full abstract»

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  • Key technologies for IMT-advanced mobile communication systems

    Page(s): 76 - 85
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (261 KB) |  | HTML iconHTML  

    WINNER is an ambitious research project aiming at identification, development, and assessment of key technologies for IMT-advanced mobile communication systems. WINNER has devised an OFDMA-based system concept with excellent system-level performance for flexible deployments in a wide variety of operating conditions. The WINNER system provides a significant step forward from current 3G systems. Key innovations integrated into the system concept include flexible spectrum usage and relaying, adaptive advanced antenna schemes and pilot design, close to optimal link adaptation, hierarchical control signaling, and a highly flexible multiple access scheme. The end-to-end performance assessment results demonstrate that the WINNER concept meets the IMT-advanced requirements. View full abstract»

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  • Completing the convergence puzzle: a survey and a roadmap

    Page(s): 86 - 96
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (254 KB) |  | HTML iconHTML  

    Convergence has more than ever been a central issue for fixed and mobile operators throughout the world and is considered to be the next big step in the evolution of telecommunication networks. Convergence opens new market opportunities and competition among network operators and above all offers enhanced user experience. Multimode handsets and the proliferation of terminals and access technologies are generating increasing demands for solutions that enable convergence, seamless handover, and transparent service delivery across heterogeneous access networks. Different strategies are available for operators, depending on the services they intend to deliver to their customers, from basic commercial convergence limited to unified billing for Fixed/Mobile/Internet up to in-dept network convergence covering new applications and services. This article surveys different technologies which offer seamless handover and converged access to mobile voice, video, and data services. It provides first the different network parts involved in defining the operator global convergence strategy and then surveys different technologies which achieve this step-by-step convergence. We present the main features of these technologies and discuss their limitations and potentials to enable convergence in heterogeneous networks. We also provide a personal stance as to the emergence of these technologies and our vision towards the long term converged telecommunication networks. View full abstract»

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Aims & Scope

IEEE Wireless Communications Magazine deals with all technical and policy issues related to personalization, location-independent communications in all media.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Hsiao-Hwa Chen
Cheng Kung University, Taiwan