Showing papers by "Deutsche Telekom published in 2000"

Robustness of DPSK direct detection transmission format in standard fibre WDM systems

Abstract: The practicability of using phase modulation in a 16 channel 10 Gbit/s system over 1600 km of standard SMF with simple dispersion compensation and the robustness in presence of ASK modulated channels has been shown for the first time.

Verfahren zur präventiven und/oder aktuellen anzeige von übertragungskosten bei der datenübertragung von internet- und onlinedaten

Abstract: Die vorliegende Erfindung schlagt zur praventiven Anzeige von Ubertragungskosten bei Internet- und Onlinediensten fur zumindest die Ubertragung groserer Datenmengen, wie beispielsweise FTP-Dateien, die Einfuhrung eines zusatzlichen Protokollelementes vor, welches anbieterseitig versendet wird, zumindest den Datenumfang der anstehenden Ubertragung sowie optional weitere Preiskriterien enthalten kann, von den an der Vermittlung beteiligten Knoten (Routern) als solches erkannt und um die eigenen anteiligen Ubertragungspreise erweiterbar ist, wobei letztlich im Empfanger-PC, beispielsweise browserseitig, eine Auswertung des Protokollelements mit demgemaser Kostenanzeige auf dem Bildschirm erfolgt, wonach der Kunde eine Ubertragung einleiten oder abbrechen kann und optional weitere Masnahmen, wie beispielsweise das automatische Einleiten der Ubertragung zu einem kostengunstigeren spateren Zeitpunkt aktivieren kann. Insbesondere ist die Einfuhrung des Protokollelements fur alle anstehenden Datenubertragungen, auch beispielsweise HTML-Pages optional sinnvoll, was insbesondere bei schnellen Internetzugangen vor der sinnlosen Zustellung umfangreich bebilderter Seiten schutzt.

Cellular phone electromagnetic field effects on bioelectric activity of human brain.

Abstract: 24 volunteers participated in the experiments. The investigation of EEG reactions to cellular phone (EMF frequency 902.4 MHz and intensity 0.06 mW/cm2) was conducted. Two experiments were performed with each subject--cellular phone exposure and Placebo Duration of the experiment was 60 min: 15 min--background; 15 min--EMF exposure or Placebo; 30 min--afterexposure. EEG was recorded in 16 standard leads with "eyes open" and "eyes closed". Special software with non-linear dynamics was developed for EEG analyses. One parameter, multichannel (global) correlation dimension, was calculated. The changes of these parameters can be evidence of brain functional state changes. As a result of EEG record processing, a significant increase of global correlation dimension during the exposure and afterexposure period was discovered, more pronounced in the case of "eyes closed". That can be viewed as the manifestation of cortex activation under phone EMF exposure.

MPEG-4 Systems: Overview

Abstract: This paper gives an overview of Part 1 of ISO/IEC 14496 (MPEG-4 Systems). It first presents the objectives of the MPEG-4 activity. In the MPEG-1 and MPEG-2 standards, “Systems” referred only to overall architecture, multiplexing, and synchronization. In MPEG-4, in addition to these issues, the Systems part encompasses scene description, interactivity, content description, and programmability. The description of the MPEG-4 specification follows, starting from the general architecture up to the description of the individual MPEG-4 Systems tools. Finally, a conclusion describes the future extensions of the specification, as well as a comparison between the solutions provided by MPEG-4 Systems and some alternative technologies.

Method and device for reducing the formation of speckle on a projection screen

Abstract: The invention relates to a method and a device for reducing the speckle that is formed on a projection display when a coherent light source (1) is used. Before being projected, the light coming from the light source strikes an electrically controllable optical element (4) with a spatially inhomogeneous index of refraction and penetrates said optical element, whereby the index of refraction within the period of projection is temporally altered. This leads to the averaging out of the speckle pattern on the projection screen (6). A multimode light source is preferably used for illumination and/or the light coming from the light source is split into several spatial modes in order to increase the effect. The light from the light source is preferably split by being coupled into a multimode light-conducting fibre. Said optical element is advantageously a liquid crystal element consisting of at least two liquid crystal layers, to which a position-dependent voltage is applied in order to produce a position-dependent index of refraction and whose birefringence is compensated by the appropriate alignment of the layers in relation to each other.

PMD compensation in 10 Gbit/s NRZ field experiment using polarimetric error signal

Abstract: A technique for compensating for the polarisation mode dispersion of a 10 Gbit/s non-return to zero (NRZ) installed fibre link (45 km, 80 ps mean differential group delay), using a variable polarisation delay line and a set of polarisation controllers is presented. The variation of the output polarisation with frequency over the signal bandwidth was monitored using a frequency-resolving Stokes-polarimeter. A control loop is used to minimise the RMS deviation of the polarisation state at the receiver.

Internationalisation of high-tech start-ups and fast growth-evidence for UK and Germany

Abstract: For firms acting in technological niches the expansion into foreign markets can be a way to increase sales and to thus to recover initial sunk costs over a shorter time frame. Our research, based on survey data for nearly 600 British and German high-tech start-ups, examines whether internationalisation leads to faster growth among high-tech start-ups. Results show that firms with international sales have higher sales growth than firms that sell only domestically. We find that technological sophistication of products and the experience of entrepreneurs has a positive impact on growth. In addition, intense competition and shorter windows of opportunity increase the pressure to grow rapidly to appropriate the returns from innovation. The findings suggest that high tech firm founders should be more determinedly international in their vision and strategies from the very start of their business to increase the economic success of their efforts.

Computational conflicts: conflict modeling for distributed intelligent systems

Abstract: 1. On Conflicts in General and their Use in AI in Particular.- 2. Conflict Ontology.- 3. Modelling Conflict-Resolution Dialogues.- 4. Managing Conflicts in Reflective Agents.- 5. Difference: a key to enrich knowledge - Concepts and Models.- 6. Detecting Temporal Conflicts in Integrated Agent Specifications.- 7. Conflict Management in Concurrent Engineering: Modelling Guides.- 8. Modeling Conflicts Between Agents in a Design Context.- 9. Conflict Management as Part of an Integrated Exception Handling Approach.- 10. Conflict Resolution in Distributed Assessment Situations.- 11. The Iterated Lift Dilemma.- References.- List of Contributors.

Implementing integrated and differentiated services for the Internet with ATM networks: a practical approach

Abstract: This article reports on design, implementation, and preliminary experimentation of a network architecture that supports quality of service for Internet applications. It gives an overview of the various approaches toward communication networks that support application-specific degrees of QoS. Special emphasis is put on the integrated and differentiated services approaches and on combinations of them. A new architecture is described which aims to bring these concepts closer to practical realization in wide-area networks. The new architecture supports the integrated as well as differentiated services approaches in a smoothly integrated way, and uses the capabilities of an underlying ATM network to realize QoS. The enhancements to the existing network infrastructure are deliberately limited to the integration of a single new type of network element called an edge device. The potential benefits of such an architecture for various stakeholders are explained, and how the new architecture could be introduced smoothly in existing networks by small migration steps, also covering networks based on technologies other than ATM. It is shown that the approach can be scaled up to a very large QoS-aware overlay network for the Internet.

On the achievable information rate with peak-power-limited orthogonal frequency-division multiplexing

Abstract: This paper addresses the problem of determining the statistical distribution of the peak-to-average power ratio (PAR) of orthogonal frequency-division multiplexing (OFDM) transmit signals. In practice, transmission systems are amplitude-limited, thus the large peak values of OFDM signals are clipped and nonlinear distortion follows. In order to avoid the resulting degradations, i.e., spectral widening and increased bit-error rate, a systematic construction of OFDM signals without large peaks is desired. The paper provides new results on the PAR distribution and hence on the achievable information rate with OFDM signals that are peak-limited. In particular, it is shown that in the case of phase-shift-keying (PSK) subcarrier modulation, the frequently applied model of Gaussian data coefficients is not appropriate. By solving an integral equation, new analytic expressions for the PAR and the achievable information rate are derived. Comparison with simulation results confirms that the new model is accurate for all ranges of practical interest.

Mobile agents and telcos’ nightmares

Abstract: The paper analyzes the current state- of- the- art of mobile agents technology wrt security, seen from the standpoint of a public network operator (pno). It is argued that the current state- of- the- art does not offer sufficient security for large- scale, commercial applications of mobile agents technology within the pno ’s networks. To support this premise, the most important security issues in this context are discussed, and a number of deficiencies are identified. Some of these deficiencies pose principal questions for future research that are not necessarily widely accepted within the agent community.

High resolution estimation of the time of arrival for GSM location

Abstract: Location services in cellular systems have become more and more important. One of the reasons is the Federal Communications Commission's (FCC) requirement to determine the position of a mobile user within an root-mean-square accuracy of 125 meters. A number of location techniques are based on the estimation of the time of arrival (TOA) or the time difference of arrival (TDOA) of the line-of-sight (LOS) signal component. However, due to multipath propagation and the limited bandwidth available in GSM or in other narrowband systems, an accurate TOA-estimation using conventional methods is hardly achievable. In this paper TOA-estimations using the modified-least-squares-Prony (MLS-Prony) and the Root-MUSIC techniques are presented. Moreover, the performance of both techniques is evaluated through simulations of a GSM transmission over different multipath channels.

Downlink beamforming for mobile radio systems with frequency division duplex

Abstract: The capacity of cellular mobile radio systems can be increased with smart antennas. The following two concepts can be utilized. First, smart antennas enable the concept of space division multiple access (SDMA) so that transmission from a base station to several mobiles at the same time and carrier frequency is possible. Second, cochannel interference in cellular systems can be reduced so that the frequency reuse is improved. The purpose of downlink beamforming is to transmit as much power as possible to the desired mobile and as little power as possible to any undesired mobile. In the case of systems with frequency division duplex (FDD) the fast fading processes for uplink and downlink are different. But, if the frequency separation is not too large, the uplink and downlink waves exhibit the same directional dependence. Therefore, downlink beamforming has to be carried out in an average sense based on the uplink channel measurements. The paper discuss the optimization of downlink beamforming for systems with FDD. It answers the question whether beamforming should be optimized in such a way that the transmitted power is mainly sent into the direction of the path with minimum average attenuation or whether it is better to distribute the power to all desired paths. The advantage from concentrating the power to the main path is that the interference power to other mobiles may be reduced due to a higher degree of freedom for beamforming. In the case of power distribution on all paths, the advantage from higher path diversity may be obtained.

Secure interoperation between 2G and 3G mobile radio networks

Abstract: Interoperation of 2G and 3G networks will be an important issue when both kinds of networks will exist in parallel and need to interwork with each other. Among other things, this implies that 2G subscribers should be able to access 3G networks by means of a 2G SIM card and a dual-mode handset. However, it is well known that 3G networks will offer its users an increased level of security when compared to 2G networks. For example, in 3G networks there will be mutual authentication between user and network as well as integrity protection of signalling commands on the air interface, with an associated 128 bit integrity key. Also the 3G cipher key will be 128 bit long, as opposed to the 2G cipher key of 64 bit length. The paper concentrates on the security aspects of 2G and 3G interworking. We identify all relevant roaming and handover cases between 2G and 3G networks and describe the solution for handling the cipher and integrity keys in these cases developed by the 3GPP security group, which is the relevant standardisation body. The guiding principle was to provide 3G security to 3G users whenever possible. The solution is assessed with respect to the security it offers and the signalling load it causes.

Mobile code as an enabling technology for service-oriented smartcard middleware

Abstract: Smartcards can be seen as service providing entities that implement a secure, tamper-proof storage and offer computational resources which make them ideally suited for a variety of tasks such as authentication management of personal profiles, and other kinds of secure information processing. Integration of smartcards into networked environments though, has not been achieved yet in a transparent manner. The authors describe the requirements for the design of middleware for smartcards and propose a platform for the execution of mobile code as the core of such middleware. This is in contrast to traditional architectures based on a request-broker scheme that would need huge standardization efforts to be applicable to smartcards. As an instance of such middleware, we describe our implementation which is centered around the mobile code facilities available in Java and the service trading features of Jini.

Hypertext documents evaluation method using search engine, involves calculating real relevance value for each document based on precalculated relevance value and cross references of document

Abstract: The evaluation of hypertext document is carried out in three phases namely construction phase, updating phase and query phase. The real relevance value for each document is calculated based on the relevance value precalculated in construction phase and cross references of the document determined in the query phase. An index server evaluates the hypertext document in three phases namely construction phase, updating phase and query phase. In the construction phase, a new document entry is applied for each address determined by the identified index references. A new term entry is applied for each identified concept, if specially marked test contents are identified in the document and a partial reference value is precalculated for each concept. In the updating phase, the documents whose contents are changed, are separated and the relevant term entries are updated. In the query phase, data are determined from the indexing component depending on the type of query such as simple query, complex query, Bootsche query or phrase query.

Mobile phone with integrated printer for printing of text, SMS, or Internet pages received with a WAP enabled phone, improving the ease and range of use of a mobile phone for minimal cost

Abstract: Mobile telephone with a display and message memory for storage or alphanumeric documents or graphical messages that can be displayed on the screen. The phone also has an integrated printer for printed output of documents or messages stored in memory.

Business models for coordinating next generation enterprises

Abstract: Today most medium sized companies just start trying to optimize the coordination of their supply chain and the communication with their internal and external customers by using electronic networks together with electronic commerce techniques. However, the great majority of these enterprises are not exhausting the full potential that advanced support concepts like modern business to business coordination allow. First steps usually include the introduction of standard groupware applications and collaboration tools, e.g. company wide directory services, email, common server workspaces, shared timers, and organizers as a needed foundation to offer support for any distributed project or team structures. Those services are only semi-integrated on a low level within individual scope rather than an automated integration with all interaction processes. A more advanced component-based approach like taking active, adaptive, and automated agent technology for (semi-)automatic coordination of business tasks and distribution of information throughout the whole production networks allows for fall back concepts and ad-hoc workflow management. In addition, it sets up the basis for a successful knowledge management. Although these concepts have been addressed for some time in the scientific community, they still have not found their way into the business coordination within production networks. We present an approach on how to integrate some of these concepts into next generation business models that are characterized by electronic collaboration and the ongoing emergence of electronic markets.

The Challenges of CORBA Security

Abstract: Large, distributed applications play an increasingly central role in today’s IT environment The diversity and openness of these systems have given rise to questions of trust and security It is the aim of the project Secure TINA to examine exactly these questions and try to find possible solutions The focus lies on OMG’s Common Object Request Broker Architecture (CORBA) as a basis technology for developing distributed systems and on the Security Service specified for it, since this seems to be the most promising technology in the field The followed approach is thereby twofold At first, a thorough analysis of the specification itself and known implementations thereof is performed, based also on experiences in the broader area of distributed systems security At a second, more practical stage, the attempt to develop an own, prototypical implementation of CORBA Security is undertaken, with the main objective of gaining as much practical experience as possible and experimenting with possible alternatives to find a solution to the problems encountered

Does R&D-Infrastructure Attract High-Tech Start-Ups?

Abstract: Our research, based on the ZEW-Foundation Panel East, examines whether high-tech start-ups are mainly founded in scientific and infrastructural well suited regions or not. Estimation results on the level of postcode areas confirm the hypothesis that specific human capital, knowledge spillovers at higher-education institutions are more important for founding a firm in one of the high-tech sectors compared with the effects of other publicly financed institutions. The existence of large companies in the manufacturing sector has a considerable effect for start-up activities in this region in general. Moreover, high-tech start-ups are more concentrated within or near technology and foundation centres.

Method and system for improving communication in a vehicle

Abstract: An embodiment and/or method to improve communication in a vehicle. Voice signals of the occupants of a vehicle may be picked up on an individual basis via separately arranged microphones. The individually picked-up voice signals may then be amplified separately for each occupant in an input stage and filtered for purposes of minimizing interference levels and for frequency adaptation. The signals may be subjected in a process stage to a signal processing that may be specific to each output channel, in the form of a delay correction and a level differentiation. And, via an adaptation stage having a level adaptation, the signals may then be distributed to likewise separately assigned loudspeakers, in accordance with the spatial conditions of the vehicle and the desired loudness level. The embodiment and/or method may be effectively used in passenger cars, larger vehicles including multimedia buses and trucks, ships, trains and airplanes/airborne spaces.

Method for billing internet transactions via mobile radio telephone service

Abstract: The invention relates to a method for billing internet transactions via mobile radio telephone service. By using WAP (Wireless Application Protocol), it is possible to select and, optionally, reserve goods and services (information, tickets, CD"s, hotel rooms, etc ) sold via the internet. When the customer decides to purchase the good or service, he or she conducts a payment transaction from the mobile radio telephone device. According to the invention, the customer data required for conducting a payment transaction is centrally maintained in a database of a payment gateway.

Mobile telephone with integral reader

Abstract: Mobile phone has scanner or barcode reader, integral with phone or detachable with connecting cable or infrared interface. Phone menu provides choice of scanner and its functions for text recognition, bar code recognition and symbol recognition. Mobile phone has scanner or barcode reader, integral with phone or detachable with connecting cable or infrared interface. Phone menu provides choice of scanner and its functions for text recognition, bar code recognition and symbol recognition. Handwritten or printed text is scanned in and integral optical character recognition software, on SIM or permanent in phone, recognizes characters. Recognized text is shown on phone display, confirmed by user and transmitted. Set text converted to bar code is scanned by bar code reader integrated in phone to transmit specific messages.

Enhancing Preprocessing in Data-Intensive Domains using Online-Analytical Processing

Abstract: The application of data mining algorithms needs a goal-oriented pre-processing of the data. In practical applications the preprocessing task is very time consuming and has an important influence on the quality of the generated models. In this paper we describe a new approach for data preprocessing. Combining database technology with classical data mining systems using an OLAP engine as interface we outline an architecture for OLAP-based preprocessing that enables interactive and iterative processing of data. This high level of interaction between human and database system enables efficient understanding and preparing of data for building scalable data mining applications. Our case study taken from the data-intensive telecommunication domain applies the proposed methodology for deriving user communication profiles. These user profiles are given as input to data mining algorithms for clustering cutomers with similar behavior.

Detecting, analyzing, transmitting, outputting scent involves acquiring, analyzing caller's scent in terminal, transmitting data to remote terminal for decoding, mixing, dispensing scent

Abstract: The method involves acquiring and analyzing the individual scent of a caller using a scent sensor (2) in a telecommunications terminal (1), encoding the data in integral coding software and transmitting it to a receiver with voice and/or image data over a network for decoding and transmission to a scent mixer that mixes the scent using the decoded data and outputs the scent via an integral miniature nozzle. Independent claims are also included for the following: an arrangement for detecting, analyzing, transmitting and outputting scents or odors or for harmful gases.

Downlink beamforming for frequency-duplex systems in frequency-selective fading

Abstract: Downlink beamforming is analyzed for broadband frequency-duplex systems where frequency-selective fading dominates. In order to compare different beamforming strategies, system level simulations are carried out. It is assumed that at the receiver of the mobile station, path diversity can be exploited. The performance gain from maximal ratio combining of the signal components is evaluated with a new approach that combines system level simulations with an analytical calculation of the probability density function of the signal-to-interference power ratio (SIR) at the output of the combiner.

Verfahren und Anordnung für den Schutz der Daten auf einer Smartcard

Abstract: An den Kontakten der externen Stromversorgung fur eine Smartcard sind mit geeigneter Mestechnik Ruckschlusse auf die verarbeiteten Daten des internen Mikrochips moglich - Differential Power Analysis (DPA). Um einen Misbrauch von Smartcards auszuschliesen, mus die DPA wirkungsvoll verhindert werden. DOLLAR A Mit der vorliegenden Erfindung wird eine DPA dadurch verhindert, das die Versorgungsspannung fur den aktiven Rechnerchip wahrend der Berechnung der vertraulichen Daten von der externen Stromversorgung fur die Smartcard entkoppelt wird. Die technische Losung kann durch eine integrierte Batterie, eine Gleichspannungsstabilisierung oder ein integriertes HF-Schaltnetzteil erreicht werden. DOLLAR A Bei Verwendung der Gleichspannungsstabilisierung oder eines HF-Schaltnetzteils kann die Versorgungsspannung fur den aktiven Rechnerchip uber einen zufallsgesteuerten elektronischen Schalter gefuhrt werden, so das zusatzlich eine Verschleierung der an den Smartcardkontakten noch zu messenden Impulse erreicht wird.

On conflicts in general and their use in AI in particular

Abstract: Conflicting situations are not only a driving force in nature, they are also the entry points for many investigations in AI. Especially conflict resolution techniques and conflict management approaches are studied in AI subfields like Expert Systems, Planning, Design, Knowledge Acquisition, Knowledge Representation, Natural Language Processing, Game-theory, Computer Simulation Study of Social Dynamics and intensively in Distributed AI, formal models of rational action, CSCW, Concurrent Engineering and HCI. Though the research on argumentation, resolution and management of conflicts grows, the essential question about what a conflict is, remains misty.

Method for the voice-operated identification of the user of a telecommunication line in a telecommunications network during an interactive communication using a voice-operated conversational system

Abstract: The invention relates to a method for the voice-operated identification of the user of a telecommunication line in a telecommunications network during an interactive communication using a voice-operated conversational system. According to the invention, during a person-to-person and/or person-to-machine conversation, the verbal expressions of a caller in a group of callers that is restricted to a telecommunication line are used to create a reference pattern for the user. A user identification is stored for each reference pattern. Said identification is activated after recognition of the user and, together with the CLI or ANI, is made available to a server with a voice-operated conversational system. Data for this user, which has already been saved using the CLI with user identification is determined by the system and made available for the interaction with the client. The inventive method can be advantageously used in voice-operated conversational systems.