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Showing papers on "Mobile technology published in 1998"


Proceedings ArticleDOI
25 Oct 1998
TL;DR: The design and implementation of an innovative trartspori level protocol capable of significantly reducing the power usage of the communication device and addressing the tradeoff between reducing power consumption and reducing delay for incoming data is addressed.
Abstract: In mobile computing, power is a hmited r=ouce. Like other devices, communication devices need to be prop erly managed to conserve energy. In this paper, we prment the design and implementation of an innovative trartspori level protocol capable of significantly reducing the power usage of the communication device. The protocol achieves power savings by selectively choosing short periods of time to suspend communications and shut down the communication device. It manages the important task of queuing data for future dehvery during periods of communication suspension, and decides when to restart communication. We *O address the tradeoff between reducing power consumption and reducing delay for incoming data. We present resdts from experiments using our implementation of the protocol. Th=e experiments measure the energy consumption for three simrdated communication patterns and compare the effects of different suspension strategies. Our r-tits show up to an 83~0 savings in the energy consumed by the communication. This can translate to a 6-9% savings in the energy consumed by an entire high end laptop or a savings of up to 40% for current hand-held PCs. The resdting delay introduced is sm~ (0.4-3.1 seconds depending on the power management level).

315 citations


Patent
Jay Franklin McLain1
08 Sep 1998
TL;DR: In this paper, a method and system for transferring offline browsing content information of a wide area network from a host computer to a mobile device includes connecting the mobile device to the host computer and obtaining characteristic information of the mobile devices pertaining to at least one of hardware and software capabilities.
Abstract: A method and system for transferring offline browsing content information of a wide area network from a host computer to a mobile device includes connecting the mobile device to the host computer and obtaining characteristic information of the mobile device pertaining to at least one of hardware and software capabilities of the mobile device. The content information is transferred from the host computer to the mobile device as a function of the characteristic information.

254 citations


Patent
15 Jan 1998
TL;DR: In this article, an apparatus and a method route information to a mobile unit in a data communications system having a home network and a remote network, where the mobile unit has a unique address and may roam from the home network to the remote network.
Abstract: An apparatus and a method route information to a mobile unit in a data communications system having a home network and a remote network. Each of the home and remote networks supports one or more mobile units and one or more stationary access points. The mobile unit has a unique address and may roam from the home network to the remote network. The mobile unit associates with one access point which serves as a home agent. When the mobile unit roams and is away from its home network, the apparatus discovers a physical location of the mobile unit by sending an agent advertisement packet from the access point. If the location of the mobile unit is not at the home network, the apparatus associates the mobile unit with one of the access points on the foreign network which serves as a foreign agent. Next, the apparatus registers the mobile unit with the home agent, encapsulates original data received by the home agent which is destined for the mobile unit, forwards encapsulated data to the foreign agent, and converts the encapsulated data to the original data and delivers the original data to the mobile unit via the foreign agent.

227 citations


Journal ArticleDOI
TL;DR: This work presents the design, implementation, and evaluation of mobiware, a mobile middleware toolkit that enables adaptive mobile services to dynamically exploit the intrinsic scalable properties of mobile multimedia applications in response to time-varying mobile network conditions.
Abstract: Existing mobile systems (e.g., mobile IP, mobile ATM, and third-generation cellular systems) lack the intrinsic architectural flexibility to deal with the complexity of supporting adaptive mobile applications in wireless and mobile environments. We believe that there is a need to develop alternative network architectures from the existing ones to deal with the tremendous demands placed on underlying mobile signaling, adaptation management, and wireless transport systems in support of new mobile services (e.g., interactive multimedia and Web access). We present the design, implementation, and evaluation of mobiware, a mobile middleware toolkit that enables adaptive mobile services to dynamically exploit the intrinsic scalable properties of mobile multimedia applications in response to time-varying mobile network conditions. The mobiware toolkit is software-intensive and is built on CORBA and Java distributed object technology. Based on an open programmable paradigm developed by the COMET Group, mobiware runs on mobile devices, wireless access points, and mobile-capable switch/routers providing a set of open programmable interfaces and algorithms for adaptive mobile networking.

175 citations


Journal ArticleDOI
B. Kreller1, A.S.-B. Park, J. Meggers, G. Forsgren, Ernö Kovacs, M. Rosinus 
TL;DR: The ongoing European ACTS project OnTheMove provides support services for distributed mobile multimedia applications by defines, implements, and demonstrates a mobile middleware called a Mobile Application Support Environment (MASE) which is based on UMTS concepts.
Abstract: The ongoing European ACTS project OnTheMove provides support services for distributed mobile multimedia applications. The project defines, implements, and demonstrates a mobile middleware called a Mobile Application Support Environment (MASE) which is based on UMTS concepts. The mobile application programming interface (mobile API) of MASE, which will be submitted for standardization, allows common access to the underlying operating systems and network infrastructure, and facilitates the development of new, mobile-aware, multimedia applications.

151 citations


Proceedings ArticleDOI
25 Oct 1998
TL;DR: Two network layer me&anisms are introduced to ensure a mobile host’s convenient and efficient communication with other hosts in a &anging environment and how they are implemented are described.
Abstract: Fueled by the large number of powerful tight-weight portable computers, the expanding availability of wirel= networks, and the popularity of the Internet, there is an increasing de mand to connect portable computers to the Internet at any time and in any place. However, the dynamic nature of such connectivity requires more flexible network support than has typically been atiable for stationary workstations. ThM paper introducw the following two me~anisms, in the context of Mobile 1P [24], to ensure a mobile host’s convenient and efficient communication with other hosts in a &anging environment. One me&anism supports multiple packet defivery methods (such as regular 1P or Mobile 1P) and adaptively selects the most appropriate one to use Wcordlng to the char=teristim of eti trfic flow. The other medanism enables a mobile host to make use of multiple wtive network interfww simultaneously and to control the selection of the most dwirable network interfaces for both outgoing and incoming pdets for different traffic flows. We demonstrate the usefdnm of these two network layer me&anisms and describe how they are implemented.

101 citations


Patent
03 Aug 1998
TL;DR: In this paper, a mobile IP communication scheme is proposed in which a visited site or nearby network of a mobile computer is utilized as a temporal home network of the mobile computer. But this scheme requires the user to exchange a message with a mobile management device provided in a nearby network from the visited site, so as to acquire a network configuration information.
Abstract: A mobile IP communication scheme in which a visited site or nearby network of a mobile computer is utilized as a temporal home network of a mobile computer. The mobile computer exchanges a message with a mobile computer management device provided in a visited site or nearby network from a visited site, so as to acquire a network configuration information of the visited site or nearby network, and sets the acquired network configuration information in a communication program to be used in carrying out communications. The mobile computer management device leases a temporal home address to be used by an externally located mobile computer in response to a request message from the mobile computer, and registers the mobile computer as a mobile node which regards a network to which the mobile computer management device belongs as a home network, in response to a registration message from the mobile computer.

80 citations


Proceedings ArticleDOI
19 Oct 1998
TL;DR: The paper describes the mobile information and communication aspects of a next generation train maintenance and diagnosis system, discusses the working prototype features, and research results.
Abstract: The paper describes the mobile information and communication aspects of a next generation train maintenance and diagnosis system, discusses the working prototype features, and research results. Wearable/Mobile computers combined with the wireless technology improve efficiency and accuracy of the maintenance work. This technology enables maintenance personnel at the site to communicate with a remote helpdesk/expertise center through digital data, audio, and image.

79 citations


01 Jan 1998
TL;DR: The paper evaluates the outcome of the labs and the requirements of commercial usage, and a system architecture is proposed from the technical perspective that leads to the discussion of the prototype developed on the Mobile Guide test-bed.
Abstract: Location-Aware applications for supporting the mobile user have proven significant relevance for future telecommunication and computing. Based on the state-of-the-art analysis and the business view, the paper evaluates the outcome of the labs and the requirements of commercial usage. A system architecture is proposed from the technical perspective. The required support of heterogeneous resources leads to the necessity of an adequate middleware platform. Merging data from different sources and constraints in the transmission and presentation capabilities of the mobile side require sophisticated media scaling and conversion capabilities. The envisaged service architecture leads finally to the discussion of the prototype developed on our Mobile Guide test-bed.

74 citations


Book ChapterDOI
19 Nov 1998
TL;DR: In this article, the authors propose an object-oriented framework for content adaptation in the Web. To facilitate the use of this framework in the web, they base their approach on the objectoriented WebComposition model and its XML-based implementation WCML.
Abstract: It is widely acknowledged that information such as web content should be adapted for mobile platforms to account for restrictions in mobile environments. As emerging mobile platforms such as different kinds of Personal Digital Assistant (PDA) tend to vary largely in their capabilities, we suggest that adaptation should be platform-specific. Common approaches for content adaptation are automated conversion and explicit specification of adapted content, with a trade-off between quality and development/maintenance effort. As alternative avoiding this trade-off, we propose a simple object-oriented framework for content adaptation. To facilitate the use of this framework in the Web, we base our approach on the object-oriented WebComposition model and its XML-based implementation WCML. We apply our object-oriented approach to an example application to demonstrate how object-oriented specification of platform-adapted content reduces development/maintenance effort.

69 citations


14 May 1998
TL;DR: This paper builds on the experiences gained from the extensive work carried out during the MOST project, which investigated the use of mobile technologies to support multimedia collaboration between highly mobile field engineers in the safety critical domain of the U.K. power distribution industry.
Abstract: This paper builds on the experiences gained from the extensive work carried out during the MOST project [MOST,95]. This project investigated the use of mobile technologies to support multimedia collaboration between highly mobile field engineers in the safety critical domain of the U.K. power distribution industry. The MOST team developed a prototype distributed groupware application which was arguably the first collaborative mobile application ever built that was capable of adaption in a mobile environment [Cheverst,94]. The application was designed as an expandable toolkit comprising a number of modules including a shared GIS module. This module enabled groups of field engineers to perform spatially-aware collaboration by supporting the display and annotation of network schematics across groups. The MOST application was evaluated by real end-users in a trial scenario using the GSM service for communications. This evaluation provided a valuable set of implications regarding the development of distributed groupware in conjunction with mobile technologies.

Proceedings ArticleDOI
25 Oct 1998
TL;DR: This paper proposes an efficient solution to undeniable b]~ng when a mobile user roams into foreign networks by the combination of digitd signature and hash-chaining techniques.
Abstract: In the current mobile communication networks, users have to trtistnetwork operators to make correct. charges over the cds they made. There islack of evidence to resolve possible disputti+ over thenurnberofcdls and the duration of each cd. Such a concern may grow when users roam among different network operators. This paper proposes an efficient solution to undeniable b]~ng when a mobile user roams into foreign networks. This is achieved by the combination of digitd signature and hash-chaining techniques. Mobile users need to submit a digitd signature when requesting a cd and release chained h~

Patent
02 Feb 1998

Proceedings ArticleDOI
01 Jan 1998
TL;DR: Experiments show that information browsing is possible with an overhead of less than 50% on the usual “mouse and scroll bar” method, and NaviPoint is a specialized device for mobile information browsing.
Abstract: A mobile computing environment imposes various restrictions on users. For example, most mobile devices have a liited screen size, and it may be di&ult to watch the screen closelyWhile the user is walking or standing in a bus or train, he or she may have only one hand free to manipulate the device. Therefore, some new operation method must be developed for comfortable information browsing in the mobile environment. In this paper, several existing methods are first introduced and compared from the viewpoint of their applicability in a mobile environment. A new input device for such an environment, named WaviPoint,” is then introduced NaviPoint is a specialized device for mobile information browsing. By using this device, a user cau perform three types of input “analog input,” “digital input.,” and “click input?’ with just one finger. After an explanation of the conceptual structure and a qualitative analysis of NaviPoint, the structure of a prototype is described Experiments using the prototype show that information browsing is possible with an overhead of less than 50% on the usual “mouse and scroll bar” method

Patent
12 Nov 1998
TL;DR: In this paper, a mobile host given an Internet Protocol address uses an existing Code Division Multiple Access type mobile network and an Home Location Register and an Inter-Working Unit in a personal communication system network to establish communications without restricting a host to a particular network.
Abstract: Mobile Internet system and method in a mobile communication network is disclosed, in which a mobile host given an Internet Protocol address uses an existing Code Division Multiple Access type mobile network and an Home Location Register and an Inter-Working Unit in a personal communication system network to establish communications without restricting a mobile host to a particular network. The mobile Internet system and method includes a plurality of mobile hosts, a plurality of mobile access points, a mobile router, and a plurality of gateway routers.

Journal ArticleDOI
TL;DR: An agent based pre-fetcher application where an agent operaes disconnected from the user on the fixed network and prepares web pages for the anticipated next connection of the user using the Quality-of-Service trading functions available in MASE.
Abstract: Mobile agents are a new paradigm for distributed computing that is especially well suited for mobile computing over global wireless networks. This paper describes the approach taken in the ACTS On TheMove project to integrate a mobile agent system into the Mobile Application Support Environment (MASE), a middleware for mobile computing. In this project, an existing mobile agent system was adapted for the requirements of mobile computing. We present the changes that had to be made to the agent system to adapt it to the wireless communication. We also present some of the application areas where a mobile agent system is suitable for mobile communication. We describe an agent based pre-fetcher application where an agent operaes disconnected from the user on the fixed network and prepares web pages for the anticipated next connection of the user using the Quality-of-Service trading functions available in MASE.

Proceedings ArticleDOI
01 May 1998
TL;DR: The design and implementation details of MAGENTA (Mobile AGENT environment for distributed Applications) are described and the mechanisms it provides for enabling applications supporting mobile users and the performance evaluation results of MAGentA are presented.
Abstract: Mobile agents based computing has been propounded as the possible approach to next generation computing. The approach has been shown to be e ective in di erent domains, especially in the area of mobile and partially connected computing. We describe the design and implementation details of MAGENTA (Mobile AGENT environment for distributed Applications) and the mechanisms it provides for enabling applications supporting mobile users. MAGENTA is a generic mobile agent environment and provides the agents the capabilities of autonomy, reactivity, proactivity and communication. In order to demonstrate the functionalities provided by MAGENTA to mobile users we have applied it in the domain of network management in order to implement a Mobile Network Manager (MNM). We also present the performance evaluation results of MAGENTA.


Proceedings ArticleDOI
27 Feb 1998
TL;DR: A cost model for query optimisation incorporating mobility specific factors like energy and connectivity is presented and the critical factors for adapting a query processing subsystem to the employed location management strategy are identified.
Abstract: Query processing in mobile database systems is a special challenge because we have to consider the limited resources of mobile systems as well as the changing location of mobile users. In this paper, we concentrate on the optimisation of queries including location information. We present a cost model for query optimisation incorporating mobility specific factors like energy and connectivity. Furthermore, we examine different localisation strategies for mobile users. This innovative connection of both factors is studied using two typical classes of queries. Using a newly developed simulation model, we describe that no single localisation strategy performs acceptable under every condition. We therefore identify the critical factors for adapting a query processing subsystem to the employed location management strategy. 1 I n t r o d u c t i o n The development of wireless communication systems and lightweight computers has led to the availability of a research area called mobile computing. The subject of research is the effect of mobility on systems, users, data and computing. In the area of database systems, mobility offers access to information anywhere and anytime. In order to access information, we have to consider the query processing in mobile database systems as one major task. Queries in mobile systems are different from stationary systems. There, location awareness adds power to the mobile user but also adds complexity to the query processPermission to make digital/hard copy of all or part of this work for personal or classroom use is granted without l~e provided that copies are not made or distributed lbr profit or commercial advantage, the copyright notice, the title of the publication and its date appear, and notice is given that copying is by permission of ACM. Inc. To copy otherwise, to republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. ,: 1q98 ACM 0-89791-969-6/98/0002 3.50 ing. Examples of location aware queries in mobile database systems are traffic information systems that give the user information with respect to his current location ("where is the next pub serving Becks beer") or queries retrieving data from mobile users whose location needs to be looked up. Apart from this new kind of queries, mobile systems pose even more new requirements on the query processing subsystem of a mobile database because of the limited resources available on typical mobile computers. Therefore, query subsystems of mobile databases have to be modified compared to stationary query processors [4]. Additionally, location information about mobile users must be categorised as only temporarily valid since mobile users may move and data on their actual location has to be updated in order to address them properly. The location management component is responsible for the storage of current location information. Ad hoc queries that use location information about mobile users have to access the location management component. Depending on the used localisation strategy, we have different costs associated with processing this kind of query. Therefore, an optimal query processing subsystem of a mobile database has to take the strategy used by the location management component into account for answering queries. In this paper, we present a new approach to the integration of these two components. We pay special attention to the usage of fuzzy information as provided by many real-world location management components. Starting by an introduction to existing location management and mobile query processing strategies in the next section, we afterwards present a new abstract model for representing mobile systems and location management components. In section four, we discuss our approach to location aware query optimisation in mobile database systems. For this, we have developed a mobility aware cost model for processing location dependent queries. To validate the model,

Dissertation
01 Jan 1998
TL;DR: Evidence shows that there is no significant difference in performance on the Chording Glove while standing or sitting, implying that the device is as mobile as intended, and the main concept behind this thesis is that, in order for wearable computers to be effective, they need to throw away the mouse and keyboard interfaces in favour of a new style of input.
Abstract: 3 Computers have been progressively becoming smaller and more mobile. The past few years have seen computers evolve from the desktop to the notebook to current handheld systems. Each new device is more portable and less cumbersome than last. The next step in this progression is the wearable computer: a computer consisting of parts small enough to be worn as clothing or accessories. However, the portability gained from a wearable computer is lost if the input devices are no smaller than existing ones. The main concept behind this thesis is that, in order for wearable computers to be effective, they need to throw away the mouse and keyboard interfaces in favour of a new style of input. These new interfaces should be designed to be easily transportable, quickly accessible, easily usable in a variety of environments , and minimise interference with " real world " interactions. In order to test this theory we have built a graphic (Biofeedback Pointer) and a text input device (Chording Glove) based on these design principles. These devices are designed to work in tandem, with the Chording Glove's text input complementing the Biofeedback Pointer's graphic input. The Chording Glove is a text input device made from mounting the keys of a chord keyboard onto the fingers of a glove. Chords are made by pressing the fingers against a firm surface. After 11 hours of use, the average input speed on the Chording Glove was 16.8wpm, with an error rate of 17.4%. The Chording Glove's entire 97 character keymap takes, on the average, 80 minutes to learn, with users needing to look up chords around 0.5% of the time after 6 hours of use. There is evidence of keymap retention after significant absence from the device, but this remains to be proven. Evidence also shows that there is no significant difference in performance on the Chording Glove while standing or sitting, implying that the device is as mobile as intended. The Biofeedback Pointer is a graphic input device controlled by wrist motion. Moving the wrist causes the pointer to move in that direction. The pointer works by measuring the Electromyograms (EMGs) of four of the main muscles used to move the wrist. This data is interpreted by a neural network which is trained for each user. The network takes about half a minute to learn to recognise the user's EMG signals. After the training the user …

Journal ArticleDOI
TL;DR: The authors present the design of a communication layer for mobile computing that dynamically adapts to changes in network connections, to allow existing TCP/IP based applications to be used in a mobile environment, without application modifications.
Abstract: Most network applications assume continuous connectivity-an assumption that does not "migrate" to wireless environments. The authors present the design of a communication layer for mobile computing that dynamically adapts to changes in network connections. Our work was part of AMIGOS (Advanced Mobile Integration in General Operating Systems), a collaboration between researchers at the University of Copenhagen in Denmark and the University of Minho in Portugal. The AMIGOS project provides transparent support for semi connected operations on mobile computers running a standard operating system; the project home page is at http://www.econ.cbs.dk/people/birger/AMIGOS/. Briefly, our design lets a mobile user connect a mobile host to a LAN, then disconnect the host from it. The user then can reconnect, for example, via a Global System for Mobile Communications (GSM) cellular modem without losing TCP/IP connections. We want to allow existing TCP/IP based applications to be used in a mobile environment, without application modifications.


Proceedings ArticleDOI
25 Oct 1998
TL;DR: In this work, the Stratosphere project, a framework which unifias distributed objects and mobile code applications, is described, which provides an object model that permit objects to migrate to different sites, select among different method implementations, and provide new methods and behavior.
Abstract: We describe the dmign and implementation of our Stratosphere project, a framework which unifias distributed objects and mobile code applications. We begin by first examining dfierent mobile code parad]gms that distribute pr~ cessing of code and data resource components across a network. After analyzing these paradigms, and prwenting a lattice of functionality, we then develop a layered architecture for Stratosphere, incorporating higher levels of m~ bilit.y and interoperabifity at each successive layer. In our design, we provide an object model that permiti objects to migrate to different sites, select among different method implementations, and provide new methods and behavior. We describe how we build new semantics in each software layer, and finally, we present sample objects developed for Stratosphere.

Proceedings ArticleDOI
16 Apr 1998
TL;DR: This paper proposes a new message delivery algorithm that requires no tracking and provides stronger guarantees than existing protocols and includes a proof outline using the UNITY logic.
Abstract: With recent advances in wireless communication and the ubiquity of laptops, mobile computing has become an important research area. An essential problem in mobile computing is the delivery of a message from a source (stationary or mobile) to a desired mobile unit. Standard solutions used in Mobile IP and cellular phones rely on tracking the mobile unit. Tracking solutions scale badly when mobile units move frequently. Our paper proposes a new message delivery algorithm and includes a proof outline using the UNITY logic. Our algorithm requires no tracking and provides stronger guarantees than existing protocols.

Proceedings Article
01 Jan 1998
TL;DR: W 3 IQ is presented, a system which supports mobile access to the web using asynchronous collaborative information retrieval techniques and its architecture, software implementation, and its capabilities as an information ltering mechanism are described.
Abstract: The World Wide Web has become a global distributed information system with a rapidly increasing user community. The advent of mobile computing coupled with the recent developments in wireless communications and personal computer technology, has created a new challenging area: mobile information access. Accessing web based information sources is likely to be one of the most important applications of mobile computers. However, the software and protocols associated with the WWW were designed with static hosts in mind. The resource limitations of mobile clients, low bandwidth of the wireless network and frequent disconnections are situations that existing WWW systems are ill equipped to deal with. There is a need to overcome these constraints and provide reliable information access from mobile computers. In this paper we present W 3 IQ, a system which supports mobile access to the web using asynchronous collaborative information retrieval techniques. We describe the model of W 3 IQ-its architecture, software implementation, its capabilities as an information ltering mechanism. We also present experimental results. A w ard. Support of Lycos who have allowed to access to their internal API is also acknowledged.

01 Jan 1998
TL;DR: The commonly romanced vision of a traveling executive being able to have uninterrupted, uninhibited access to his office mail, office databases, personal files, and video conferencing while moving between geographically separated customer locations, airports and hotels is a reality that will happen in the next few years.
Abstract: There is hardly a more pervasive trend in the world today than communications. The momentum towards anytime, anywhere and any-type of communication is fueled by advances in radio frequency technology, near-exponential sales of laptop computers and personal digital assistants (PDAs), as well as new models of business that expect and rely on instantaneous information availability. The commonly romanced vision of a traveling executive being able to have uninterrupted, uninhibited access to his office mail, office databases, personal files, and video conferencing while moving between geographically separated customer locations, airports and hotels is a reality that will happen in the next few years.

Book ChapterDOI
15 Jul 1998
TL;DR: This paper surveys the new challenges and the research on security issues in mobile data management, access and transfer, and identifies a basic characteristic of these security issues, adaptability, to answer the dynamics.
Abstract: Mobile computing and communication is a rapidly developing area. But mobility is associated with problems for security and privacy beyond those in open networks. A well known threat is tracking user movements. New risks are caused by the mobility of users, the portability of computers, and wireless links which include dynamics, resource dependencies and additional information to ensure the communication. This paper surveys the new challenges and the research on security issues in mobile data management, access and transfer. We investigate the issues concerning database specific security which have to be reconsidered. We will identify a basic characteristic of these security issues, adaptability, to answer the dynamics.

01 Jan 1998
TL;DR: The explosion in mobile computing has been made possi-ble through the continued advancement of certain key tech-nological areas and it is possible to evaluate the past successes, current trends and future opportunities by considering the relationship between mobility, portability, human ergonomics and cost.
Abstract: By definition, the field of mobile computing is just as broadas traditional computing. The average consumer is especiallydemanding of technology by expecting the same convenienceand computing power in the mobile device as the computerwhich sits on the desk. Furthermore, mobility opens up newvenues for interesting and unique products and services onlypossible in a mobile environment. The potential of location-independence can barely be underestimated as freedom fromgeographic constraints can allow for a more effective, conve-nient and timely use of computing and communication. Aspeople tend to think and work in places other than at the deskin their office, mobile computing allows the use of the com-puter as a tool where it is needed, not where it is tied by a wire.Examples include the familiar executive working on a laptopwhile in transit and the field engineer having remote electro nicaccess to technical documentation and diagnostics, as well asemergingapplicationssuch as automatedinventoryorbaggagechecking with RFID devices, and location-dependent servicessuch as local maps or weather reports.Several years ago it would have been commonplace to de-fine mobile computing in terms of the laptops used. How-ever, this traditional view has changed significantly. Alre adytoday, cellular phones allow web browsing and email recep-tion, palmtop computers come with scaled down versions ofdesktop operating systems and applications, and Radio Identi-fication Devices (RFID) are providing intelligent communic a-tion and computing power with nearly any type of object. Thismyriad of new devices spans the technological and budgetaryspectrums, making it harder to attach the definition of mobil ecomputing to any single device or application. However, thereis one underlyingsimilarity among all these devices and appli-cations that allow us to simply define a mobile computer as acomputing device which can communicate through a wirelesschannel.The explosion in mobile computing has been made possi-ble through the continued advancement of certain key tech-nological areas. It is possible to evaluate the past successes,current trends and future opportunities by considering the fol-lowing areas: First, we need to consider the relationship be-tween mobility, portability, human ergonomics and cost. Forexample, in order to make a device portable it must be smalland lightweight, which precludes the use of most standardhard drive and keyboard designs. Second, a fundamental re-quirement of today’s computer is network connectivity. Thisimplies, mostly, radio-frequency wireless communications formobile devices. Although infrared mobile computer commu-nications can be also used, interference from the sun as well asthedifficultyofnon-line-of-sightcommunicationsmakeradio-frequency the preferred method for location independent mo-bile communications. Third and most important are the powerconsiderationsof mobile computers. Mobility implies relianceon a mobile portable power source in the form of a battery.Since the power available from a battery is closely related toits size and weight, it is fundamental that all the parts of themobile device are power-efficient. As battery capacities arenot expected to increase more than 30% in the near future[3],while computing capabilities and features have ever increas-ing expectations, power efficiency has become a fundamentaltechnology.

Journal ArticleDOI
TL;DR: The authors present a theoretical formulation and propose a system to disable mobile phones in designated areas and field tests are described that support the viability of the system.
Abstract: The authors present a theoretical formulation and propose a system to disable mobile phones in designated areas. Field tests are described that support the viability of the system.

Book ChapterDOI
26 May 1998
TL;DR: The basic principles of MEMO, the implementation of the second generation equipment, as well as on trial design and example services are reported on.
Abstract: The objective of the ACTS project MEMO (Multimedia Environment for Mobiles) is to develop, implement and demonstrate a communication system which brings interactive Multimedia services to fully mobile users. This is realised by combining the high-speed broadcasting facilities of DAB with a bi-directional telecommunications network like GSM. On the platform of these two European success stories three categories of services can be offered: Broadcast, Interactive Broadcast and Personal Services. Based on experience gained from first successful trials in 1996 with this platform for mobile Multimedia services a second generation equipment has been implemented using newest developments on DAB-Receivers. This paper reports on the basic principles of MEMO, the implementation of the second generation equipment, as well as on trial design and example services.