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Communications Magazine, IEEE

Issue 2 • Date Feb. 2002

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Displaying Results 1 - 20 of 20
  • QOS measurement and evaluation of telecommunications quality of service [Book Review]

    Page(s): 30 - 32
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    Freely Available from IEEE
  • Wireless LAN standards and applications [Book Review]

    Page(s): 32 - 34
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    Freely Available from IEEE
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  • Optical networking: signs of maturity [Guest Editorial]

    Page(s): 64
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    Freely Available from IEEE
  • Next-generation broadband wireless networks and navigation services [Guest Editorial]

    Page(s): 110 - 111
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    Freely Available from IEEE
  • Wireless networks based on high-altitude platforms for the provision of integrated navigation/communication services

    Page(s): 119 - 125
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2506 KB) |  | HTML iconHTML  

    Provision of telecommunication services by means of high-altitude platforms (HAPs) is becoming a relevant topic of interest for the research activities on future-generation systems. Mobility on demand, large coverage, and payload reconfigurability are only some examples of the expected benefits for personal communication systems based on the use of such platforms. The research regarding the use of HAPs for communications has so far neglected that they are also a privileged infrastructure for the provision of navigation and positioning services. They can act as augmentation infrastructures for global navigation satellite systems such as GPS and the future Galileo, easily performing direction of arrival estimation thanks to their high position, collecting and broadcasting position information. Despite these interesting services, the real added value is in the fact that their payload can easily integrate both communication and navigation services, with mutual benefits for both systems. The scope of this article is to discuss the feasibility of integrating HAPs with communication networks (e.g., UMTS) and navigation systems, providing an overview of different system aspects (payload, user segment) View full abstract»

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  • Control plane design for reliable optical networks

    Page(s): 90 - 96
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    The application of an IP-based control plane to optical networks has opened up new opportunities and challenges for network designers. Although much work has been done on standardization of protocols for IP networks, the applicability of these protocols to controlling optical networks and the overall reliability of optical networks needs further investigation. This article provides a detailed discussion of a number of subtle protocol design and implementation issues that were not addressed in early standardization efforts or published papers View full abstract»

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  • Linearized transmitters: an enabling technology for software defined radio

    Page(s): 156 - 162
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    Power amplifier and transmitter linearization techniques are now a mature technology, with feedforward systems installed in many US base station sites for both TDMA and CDMA systems. Similarly, transmitter linearization techniques, such as Cartesian loop and predistortion, have been employed in mobile and portable equipment, and these have enabled a number of systems (e.g., iDEN in the United States and TETRA in Europe) to be realizable from a power consumption, cost, and size perspective. Such techniques are essential in the realization of an efficient and cost-effective software-defined radio system, whether deployed in a base station or a handset, and are thus a key enabling technology, without which SDR will not succeed. This article examines the current status of power amplifier and transmitter linearization technologies for mobile and base station equipment, and highlights some of the novel base station and network topologies now emerging based on these techniques. In many cases, these new topologies will revolutionize the way a cellular network is constructed and lead to very substantial cost reductions for a network operator View full abstract»

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  • Designing the interworking of terrestrial and satellite IP-based networks

    Page(s): 136 - 144
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3086 KB) |  | HTML iconHTML  

    The design of effective interworking between a multimedia terrestrial backbone and a satellite access platform is a key issue for the development of a large-scale IP system designed for transporting multimedia applications with QoS guarantees. This article focuses on the design of a gateway station that acts as an interworking unit between the two segments of the systems. The guarantee of differentiated QoS for applications within the envisaged global IT system is achieved effectively by assuming that the IP IntServ model in the satellite access system is combined with a DiffServ fixed core network, in which the RSVP aggregation protocol is implemented. Thus, the design activity of the IWU mainly focuses on the following issues: seamless roaming between the two heterogeneous wireless and wired environments, efficient integration between the two IP service models (IntServ and DiffServ), and suitable mapping of terrestrial onto satellite bearer for traffic with different profiles and QoS requirements View full abstract»

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  • IPACT a dynamic protocol for an Ethernet PON (EPON)

    Page(s): 74 - 80
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3096 KB) |  | HTML iconHTML  

    We investigate design issues for access networks based on passive optical network technology. A PON based on polling, with data encapsulated in Ethernet frames, possesses many desirable qualities, such as dynamic bandwidth distribution, use of a single downstream and a single upstream wavelength, ability to provision a fractional wavelength capacity to each user, and ease of adding a new user. To support dynamic bandwidth distribution, we propose an interleaved polling algorithm called IPACT. We also suggest a scheme for in-band signaling that allows using a single wavelength for both downstream data and control message transmission. To obtain realistic simulation results, we generated synthetic traffic that exhibits the properties of self-similarity and long-range dependence. We then analyzed the network performance under varying offered loads View full abstract»

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  • Error monitoring for optical metropolitan network services

    Page(s): 104 - 109
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3274 KB) |  | HTML iconHTML  

    Service providers rely on performance monitoring capabilities not only to ensure integrity of their network but also to support service-level agreements with their customers. The depth of monitoring is directly tied to the technology and protocol used in the transport layer of the network. Next-generation services based on enterprise-centric, non-SONET/SDH protocols, such as Gigabit Ethernet and Fibre Channel, as well as managed protocol-independent wavelength transport, have created a number of challenges for service providers because of the differences in how error monitoring is performed. In this article we describe and compare protocol-dependent and protocol-independent error monitoring techniques that apply to these service offerings View full abstract»

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  • Global roaming in next-generation networks

    Page(s): 145 - 151
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2641 KB) |  | HTML iconHTML  

    Next-generation mobile/wireless networks are already under preliminary deployment. Mobile/wireless all-IP networks are expected to provide a substantially wider and enhanced range of services. However, an evolutionary rather than revolutionary approach to the deployment of a global all-IP wireless/mobile network is expected. To support global roaming, next-generation networks will require the integration and interoperation of mobility management processes under a worldwide wireless communications infrastructure. In this article global roaming is addressed as one of the main issues of next-generation mobile networks. Apart from the physical layer connectivity and radio spectrum allocation plans, mobility in a hierarchical structured scheme is discussed. An all-IP wireless/mobile network combined with inherited mobility schemes of each network layer and Mobile IP extensions is proposed. In this respect the mobility management mechanisms in WLAN, cellular, and satellite networks are analyzed, and an all-IP architecture is described and an enhanced roaming scenario presented View full abstract»

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  • Ethernet passive optical network (EPON): building a next-generation optical access network

    Page(s): 66 - 73
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3082 KB) |  | HTML iconHTML  

    This article describes Ethernet passive optical networks, an emerging local subscriber access architecture that combines low-cost point-to-multipoint fiber infrastructure with Ethernet. EPONs are designed to carry Ethernet frames at standard Ethernet rates. An EPON uses a single trunk fiber that extends from a central office to a passive optical splitter, which then fans out to multiple optical drop fibers connected to subscriber nodes. Other than the end terminating equipment, no component in the network requires electrical power, hence the term passive. Local carriers have long been interested in passive optical networks for the benefits they offer: minimal fiber infrastructure and no powering requirement in the outside plant. With Ethernet now emerging as the protocol of choice for carrying IP traffic in metro and access networks, EPON has emerged as a potential optimized architecture for fiber to the building and fiber to the home View full abstract»

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  • A framework for service-guaranteed shared protection in WDM mesh networks

    Page(s): 97 - 103
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2690 KB) |  | HTML iconHTML  

    In this article a framework for end-to-end service-guaranteed shared protection in dynamic wavelength division multiplexing (WDM) mesh networks, called short leap shared protection (SLSP), is introduced. The idea of SLSP is to divide each working path into several overlapped protection domains, each of which contains a working and protection path pair. In addition to a guaranteed restoration service, SLSP is designed to satisfy the future requirements of wavelength-routed optical mesh networks in scalability, class of service, and capacity efficiency. Tutorial-like discussions are given in the architecture design and signaling mechanisms for implementing the SLSP framework in a dynamic network environment with examples and illustrations. To show that SLSP can improve capacity efficiency, simulations are conducted using four networks (22-, 30-, 79-, 100-node) for a comparative study between ordinary shared protection schemes and SLSP View full abstract»

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  • A software solution for chip rate processing in CDMA wireless infrastructure

    Page(s): 163 - 167
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    Third-generation cellular infrastructure requires extremely high-performance signal processing in the baseband receiver. Currently, chip rate processing is implemented using FPGA and ASIC technology. The use of a digital signal processor is explored for UTRA FDD systems with the goal of reducing cost and increasing flexibility. By combining chip rate and symbol rate processing within a single platform and taking advantage of the natural capacity of the air interface, load balancing can be performed, which reduces the amount of processing power needed, thereby reducing the cost of the receiver View full abstract»

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  • JumpStart: a just-in-time signaling architecture for WDM burst-switched networks

    Page(s): 82 - 89
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (4273 KB) |  | HTML iconHTML  

    We present an architecture for a core dWDM network which utilizes the concept of optical burst switching coupled with a just-in-time signaling scheme. It is a reservation-based architecture whose distinguishing characteristics are its relative simplicity, its amenability to hardware implementation, and the ability to support multicast natively. Another important feature is data transparency-the network infrastructure is independent of the format of the data being transmitted on individual wavelengths. We present the signaling protocol designed for this architecture, as well as an unified signaling message structure to be used in conjunction with the protocol. We also present the future directions of this research View full abstract»

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  • Distributed integrated circuits: an alternative approach to high-frequency design

    Page(s): 168 - 173
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2252 KB) |  | HTML iconHTML  

    Distributed integrated circuits are presented as a methodology to design high-frequency communication building blocks. Distributed circuits operate based on multiple parallel signal paths working in synchronization that can be used to enhance the frequency of operation, combine power, and enhance the robustness of the design. These multiple signal paths usually result in strong couplings inside the circuit that necessitate a treatment spanning architecture, circuits, devices, and electromagnetic levels of abstraction View full abstract»

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  • CORBA delays in a software-defined radio

    Page(s): 152 - 155
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    The increasing processing power available in single-chip processors is the technical enabler for a software-defined radio. Previous efforts have defined a software radio architecture based on POSIX operating systems and CORBA. Although this approach successfully hides details of the underlying hardware from the application software, it raises questions concerning the delays introduced by CORBA and their impact on the radio's real-time operation. Measurements performed on a software radio indicate that CORBA-related delays are tolerable, even in a nonoptimized implementation View full abstract»

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  • MIRAI architecture for heterogeneous network

    Page(s): 126 - 134
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3754 KB) |  | HTML iconHTML  

    One of the keywords that describe next-generation wireless communications is "seamless." As part of the e-Japan Plan promoted by the Japanese Government, the Multimedia Integrated Network by Radio Access Innovation project has as its goal the development of new technologies to enable seamless integration of various wireless access systems for practical use by 2005. This article describes a heterogeneous network architecture including a common tool, a common platform, and a common access. In particular, software-defined radio technologies are used to develop a multiservice user terminal to access different wireless networks. The common platform for various wireless networks is based on a wireless-supporting IPv6 network. A basic access network, separated from other wireless access networks, is used as a means for wireless system discovery, signaling, and paging. A proof-of-concept experimental demonstration system is available View full abstract»

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  • Indoor geolocation science and technology

    Page(s): 112 - 118
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    This article presents an overview of the technical aspects of the existing technologies for wireless indoor location systems. The two major challenges for accurate location finding in indoor areas are the complexity of radio propagation and the ad hoc nature of the deployed infrastructure in these areas. Because of these difficulties a variety of signaling techniques, overall system architectures, and location finding algorithms are emerging for this application. This article provides a fundamental understanding of the issues related to indoor geolocation science that are needed for design and performance evaluation of emerging indoor geolocation systems View full abstract»

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Aims & Scope

IEEE Communications Magazine covers all areas of communications such as lightwave telecommunications, high-speed data communications, personal communications systems (PCS), ISDN, and more.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Sean Moore
Centripetal Networks