Ericsson (Norway)

In this paper, we examine how switched-capacitor (SC) converters can be used in low-voltage low-power DC/DC applications with power management. Analysis of losses is presented to facilitate SC converter design and optimization. A resonant gate drive is proposed to reduce switching losses and simplify control of switches in SC converters. A closed-loop controller is designed to enable and disable oscillations of the resonant gate drive so that the output DC voltage is well regulated down to zero load and so that high efficiency is maintained for a very wide range of loads. Results are experimentally verified on two low-power (0.2 and 5 W) five-one step-down converters with regulated 3 Vdc output and efficiency greater than 80% in a 100-1 load range.

The nature of mobile communication, characterised for example by terminals having poor user interface and limited processing capacity, as well as complex combination of network protocols, makes the design of security solutions particularly challenging. This paper discusses some of the difficulties system architects are faced with as well as some advantages mobile networks offer when designing security solutions for mobile communication.

The purpose of the study was to analyse how cross-border commuting differed from intranational commuting in Sweden, and how cross-border mobilities affected spatial integration. The authors analysed patterns and spatial flows of cross-border commuting by comparing them with characteristics of intranational commuting. In the article, they explore the assumption that the border constitutes an ‘engine’ for work-related mobility, which affects processes of spatial integration in cross-border areas. The empirical material comprised data from surveys of commuting from the Swedish county of Värmland to Norway and commuting within Värmland. The findings showed that cross-border commuting shared common features with intranational commuting, including how the frequency of commuting was dependent on distance. The motives for commuting differed, and the reasons for working in Norway were economic rather than professional. In terms of spatial integration, cross-border commuting was mainly one-directional, from Sweden to Norway, while leisure mobility and migration tended to be in the opposite direction. The authors conclude that the border region is characterised by integration through specialisation, which involves a permanent state of ‘transient’ mobility. Thus, a win-win situation can be distinguished, in which the border serves as a resource and an ‘engine’ for cross-border integration, mobility and economic activities.

Mobile communication is one of the most important applications in the tele-communications and IT field. Developments in technology are enabling the design of advanced mobile radio networks linking information processing and data routing, with the radio segment sandwiched between layers of digital signal processors. Spread spectrum technology adapts radio communication to computational data information processing networks. This book presents the concepts of modern mobile communication and discusses the user requirements and operational environment which influence mobile systems design. Its focus is on the mobility issues for a decentralised network topology and the effects of spread spectrum modulation on radios used in packet-switched networks. Connecting radio terminals using packet switching gives a highly flexible and efficient solution for mobile users, and the book gives considerable space to discussing packet switching in radio networks, protocols and routing strategies. Providing vital information for all those in the mobile systems field, the book is supported by detailed case study information to illustrate the practical issues involved in implementing the technology

Resilient packet ring (RPR, IEEE std. 802.17-2004) is a recent networking standard developed by the IEEE LAN/MAN working group. RPR is an insertion buffer, dual ring technology, utilizing a back pressure based fairness algorithm to distribute bandwidth when congestion occurs. In its attempt to control a set of nodes' sending behavior over a congested link, the RPR fairness algorithm suffers from two severe performance deficiencies. The first concerns how the node closest to a congested link calculates a fair rate estimate, the second deficiency relates to the method used to distribute this fair rate estimate to nodes upstream from the congested node. In this paper, we analyze these deficiencies and propose improvements to resolve them.

Mobile e-commerce enables the mobile user to buy and pay for things, to pay his bill or to make a bet via his mobile phone when on the move, anywhere and at any time. It will bring conveniency and contribute to improve life quality of the users. However, in order to be successful, security measures must be strong enough to protect the user from illegal abuses and to get confidence from him. Unfortunately, current security measures for mobile phones are not yet sufficient. This paper describes the R&D activities in mobile e-commerce at Ericsson, which aim at making mobile e-commerce applications secure and enabling a full scale development and deployment of them. The paper starts with a definition of mobile e-commerce. Next is a summary of the Wireless Application Protocol (WAP) and its achievements. The Web e-commerce is briefly explained. The problems related to security in mobile e-commerce are then described. Thereafter, the solution to the problems is presented. The paper concludes with a look at the future and discussions on what can be done.

Resilient packet ring (RPR) is a new standard, designated IEEE standard number 802.17, for MAN and WAN dual ring topologies. RPR uses the buffer insertion principle as a basis for its medium access control protocol. In this paper, we analyze parts of the aggressive mode of the RPR fairness protocol. We look at a congested node, and utilize control systems theory to analyze the stability of the associated fairness algorithm. In particular, we discuss how the settings of the two important parameters ageCoef and IpCoef influence the stability of an RPR-network. At the end of the paper we present simulated scenarios in order to illustrate our results.

Abstract Never before have there been so many organizations working with process improvement as today. These organizations have higher demands on the improvement concepts that they adopt from research and consulting than the ‘pioneer’ organizations had. Concepts must have a track‐record of proven success in other organizations and they should be directly transferable and adoptable. This requires packaged knowledge, ready to use and including a suitable level of support. This paper describes such packaged knowledge on how to run improvement programs and the experiences from applying it in real industrial software development organizations. This paper describes a model and method for how an organization can introduce and implement a successful improvement program. The model, named the Accelerator model, points out key activities necessary for leading an improvement program and gives recommendations on how to implement those activities based on experience and best practice. This paper also describes a method for how to apply the model to accelerate an improvement program, and finally presents real experiences from the full‐scale implementation at two of Ericsson's software design centres, one in Norway and one in Denmark. Copyright © 2001 John Wiley & Sons Ltd

With the introduction of mobile communication technology, users of telecommunication services are able to move freely around while engaged in communication over distance. This is introducing the users of mobile telecommunication services to varying contexts. Based on findings from field studies of highly mobile, and highly communication intensive activities, a contextual communication model is described. This model is enabling selection of communication media, and the selection of interaction modality based on the contextual information of the users.

SummaryAbstraction and platform are two of the most central concepts in MDA. To succeed with MDA means to build a clear, operational understanding of the two concepts. Two key questions are how to express the PIM and especially its behavior, and how to deal with implementation and platform dependent properties. In this chapter we offer some answers based on earlier work on model-driven development and current work on model-driven service engineering. A central aim of the latter work is to enable rapid, modular and incremental development and deployment of collaborative services. A model-driven solution supported by a layered execution framework is presented.

The decomposition of large systems into parts is a general principle of software design. Even more, in the scope of distributed systems, a partition of the whole system into distributable components is necessary. Decisions about what constitutes a component of a system are usually either based on the behavior or on the structure of the system. Nevertheless, there is a strong mutual influence between both kinds of decomposition. Despite the importance of structural and behavioral decomposition, many modeling notations and languages define the semantics of these concepts rather vaguely, and this may lead to incorrect implementation. This paper presents the new structuring mechanisms in the object-oriented specification and description language SDL-2000. The paper also gives a critical evaluation of these concepts and a comparison with similar approaches in UML (Unified Modeling Language) and ROOM (Real-time Object-Oriented Modeling).

The paper addresses the requirement to support component mobility. Field studies of bike messenger operations in Oslo and New York City has been conducted to inform design. We have investigated how component mobility is critical for enabling tailoring of personal mobility in general, and on-body off-body mobility specifically. We suggest that taking mobility seriously may not only contribute to our understanding of current support for mobility, but also raise more general issues concerning requirements and design of mobile technologies. Instead of building a terminal by integrating several terminals into one, our approach suggests first, a dissolution of the current terminals into pieces called "basic components" and then reassemble the selected basic components to form a customized terminal.

No abstract available.

As shown by V.T. Do and J.A. Audestad (1996), access and location transparencies defined for open distributed processing (ODP) and TINA are unsufficient to support terminal mobility since interoperability between DPE platforms is not guaranteed at all times. We study all the functions and computational objects necessary to support terminal mobility. Both forms of interactions: operational and stream oriented, are considered. The solution proposed is generic and can be customised for both continuous and discrete mobility in either wireline or wireless networks.

Modelling techniques from the telecommunication field are used to define an architecture for intelligent transportation (or advanced transport telematics) systems. The techniques give a precise and intuitive description that can exploited to define and manage a systems architecture. In contrast to conventional methods, it also provides an architectural model operating with types and instances and offers relative views through roles. Techniques demonstrated here have been used for a number of years to produce ultra-reliable software for telecommunication systems applications.

In this paper, we view mobility as a basic characteristic of telecommunication networks in order to, firstly support the type and extent of mobility required by an application and secondly make mobility transparent to it. In this sense, mobility can be viewed as a new class of transparency supported by ODP systems. In order to achieve this aim, we suggest a generic mobility model where mobility is broken down onto components such as identification, access control, authentication, location tracking, location updating, service profile management and service delivery. In order to support the mobility of an application, the necessary mobility components are selected, combined and instantiated.

Mobile e-commerce enables the mobile user to buy and pay for things, to pay his bill or to make a bet via his mobile phone when on the move, anywhere and at any time. It will bring convenience and contribute to improve life quality of the users. However, in order to be successful, security measures must be strong enough to protect the user from illegal abuses and to get confidence from him. Unfortunately, current security measures for mobile phones are not yet sufficient. This paper describes the mobile e-commerce activities at Ericsson, which aim at making mobile e-commerce applications secure and enabling a full-scale development and deployment of them. The paper starts with a definition of mobile e-commerce. Next are a summary of the Wireless Application Protocol (WAP) and its achievements. The Web e-commerce is briefly explained. The problems related to security in mobile e-commerce are then described. Thereafter, the solution to the problems is presented. The paper concludes with a look on the future and discussions on what can be done.

We view mobility support as a bridging matter between fixed and mobile domains. In single domain systems, mobility is implicitly supported by access and location transparencies provided by the distributed processing environment (DPE). Distributed telecommunication systems span, however, several domains that are controlled by different actors and may also be fixed or mobile. Mobility is no longer automatically supported since interoperability is not always guaranteed between domains. In order to provide interoperability between fixed or mobile domains, the agent concept is proposed. Mobility is, thereafter, made transparent to the applications by using the proxy concept.

A VHF tactical radio is being developed for the Norwegian Army by NFT-Ericsson. This radio has a considerable direct sequence spread spectrum (DS) processing gain in fixed frequency (FF) mode. In frequency hopping mode each hop has a DS component adding to the total jamming resistance. The services offered are combat net radio, single channel radio access, and command, control, and intelligence real-time data. The radio has been named the Multi-Role Radio (MRR). Packet radio is offered in all services. A DS/FF prototype transmitter and receiver were tested in 1988. In the field tests 2.4-kb/s data were received with a bit error rate of 10/sup -3/ or better with the same or smaller power than required by a PRC 77 for just readable voice.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Abstract. The paper describes an empirical study to investigate the state of practice and challenges concerning some key factors in reusing of in-house built components. It also studies the relationship between the companies ’ reuse level and these factors. We have collected research questions and hypotheses from a literature review and designed a questionnaire. 26 developers from three Norwegian companies filled in the questionnaire based on their experience and attitudes to component reuse and component-based development. Most component-based software engineering articles deal with COTS components, while components in our study are in-house built. The results show that challenges are the same in component related requirements (re)negotiation, component documentation and quality attributes specification. The results also show that informal communications between developers are very helpful to supplement the limitation of component documentation, and therefore should be given more attention. The results confirm that component repositories are not a key factor to successful component reuse. 1.