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The article focuses on third generation (3G) cellular systems. The goal of 3G wireless networks is to provide efficient support for both voice and high hit-rate data services. Third generation mobile and wireless networks aim to fulfill the demands of future services. 3G systems will offer global mobile multimedia communication capabilities in a seamless and efficient manner. Regardless of their location, users will be able to use a single device in order to enjoy a wide variety of applications. The term 3G is usually accompanied by some vagueness, as sometimes different people mean different things when they refer to it. 3G was originally defined to characterize any mobile standard that offered performance 3G systems will provide at least 144 kbps for full mobility applications in all cases, 384 kbps for limited mobility applications in macro and microcellular environments and 2 Mbps for low mobility applications particularly in the micro and picocellular environments.

The article presents information about the wideband Code Division Multiple Access (CDMA) network sensitivity. The approach provides a relatively simple way to specify the required quality of MAI canceller (decorrelator) and RAKE receiver in a CDMA system, taking into account all their imperfections. A flexible, complex signal format is used that enables to model all currently interesting wideband CDMA standards. For such a signal we first derive a complex decorrelator structure. This is the first time that a complete decorrelator is described for the CDMA signal with two independent data and two independent code streams. This type of the signal is used in all CDMA standards. In the next step all imperfections in the operation of such a system are modeled and analyzed by using the concept of a network sensitivity function.

Provision of the requested Quality of Service (QoS) and efficient utilisation of resources are some of the objectives of COST253. In order to achieve these challenging tasks it is necessary to analyse and/or simulate such a network before actually implementing it. Modelling services using appropriate source and traffic models are therefore very important to enable simulations and analysis to be performed with the selected network architecture. Source modelling is used to mimic the behaviour of a source. Traffic modelling on the other hand focuses on aggregated traffic patterns. Multiplexed models will capture the effects of statistically multiplexing bursty sources and will predict to what extent the combination of bursty stream is smoothed. Hence traffic models will be used for designing connection admission control algorithms and traffic engineering the network.

Chapter 1 gives a brief introduction on the evolution of satellite communications and the services being envisaged to be provided by satellite systems. A discussion on different EU initiatives in supporting the development of satellite communications is also presented. The operating frequencies of and technical issues in satellite systems operations for network interconnection are also addressed. Finally, the objectives and activities under the COST Action 253 are described. [ABSTRACT FROM PUBLISHER]

Chapter 5 deals with models for the physical layer and for user traffic generation. It is particularly useful for researchers and developers in the field of cellular communication systems, who want to assess certain performance parameters at the MAC level or the system level. The models are made use of in chapters 7 to 9. The chapter explains how to account for the multiple access interference in systems with a CDMA feature through Gaussian approximations (assuming random coding) and discusses the impact power control errors; explains how to account for intercell interference in CDMA systems; describes a simple two-state voice source model and the resulting aggregate voice traffic; describes models for non-real-time data traffic, in particular the UMTS Web browsing model and an email model proposed by the authors. [ABSTRACT FROM PUBLISHER]

Chapter 3: provides a short discussion of basic multiple access schemes (at the physical layer): CDMA, TDMA and FDMA; examines why the role of multiple access protocols (at the MAC sub-layer) is rather limited for 'plain' 2G cellular systems, but becomes much more important for 2.5G systems and beyond; reviews multiple access protocols with respect to their suitability for 3G cellular systems, more specifically for the use on common or shared channels to support packet-data traffic: ALOHA, slotted ALOHA, splitting/collision resolution algorithms, carrier sensing and channel sensing protocols, impact of packet capture, etc.; makes a case for reservation ALOHA protocols and discusses a representative of this family of protocols in more detail, namely packet reservation multiple access. [ABSTRACT FROM PUBLISHER]

The article presents the names of contributors, table of content, preface and index. The names of some of the contributors are Abdel Nasar Adas, P. Abry, O.J. Boxma, F. Brichet, J.W. Cohen, Mark E. Crovella, N.G. Duffield and others. In the preface it is mentioned that the the recent discovery of scaling phenomena in modern communication networks involving self-similarity or fractals and power-law or heavy-tailed distributions is yet another realization of Benoit Mandelbrot's vision of order in physical, social, and engineered systems characterized by scaling laws. The index lists that the activity period is mentioned in pages 185 and 262 of the articles. The word admission control is listed in pages 291, 371, 408, 412, 423, 466, 543, 548-549.