ISSN:1124-318X    

DOI:10.1002/ett.4460020202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractThe framework of the Telecommunication Project is firstly considered, by a snapshot on the evolution of public telecommunication networks towards broadband capabilities. Then, the objectives and the activities of the Project are illustred. Finally the papers of the Seminar are shortly presented.

ISSN:1124-318X    

DOI:10.1002/ett.4460020203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractThe present telecommunication evolution is driven by a very complex relationship between market forces and new advanced technologies. This process is accelerated, among other things, by regulation actions and, more important, by the availability for end users of competing alternative solutions. Aim of the paper is first to discuss some of the major requirements/opportunities ‐ from standard to business user needs, from intelligence to decentralization, from mobile to image communications. This allows setting a rationale and an overall consistent framework for the three‐yearSubproject 1: Structure of Broadband Communication Network.After a brief introduction about the innovation process in complex systems, the paper clarifies the role and the time scale for the service offering of broadband structures in telecommunication networks. The main research topics are then summarized thereby giving an introduction to the three more focused Conference papers, which consider specific relevant issues, broadband network evolution, metropolitan area networks, and satellite systems for high‐definition television (HDTV). Finally, the subproject organization, work progress and major achievements obtained in the first‐year activity are o

ISSN:1124-318X    

DOI:10.1002/ett.4460020204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractIn the Research Project on Telecommunications of the National Research Council, the area of the «Technologies for broadband optical communications» was individuated as one of the key areas for the promotion of advanced research activities and the formation of highly specialized competences in a field which will be determinant for the development of future communication networks. The subproject 2 was established on this view, and a detailed plan for researches on some relevant topics, namely the coherent techniques, the optical switching and the optoelectronic components, has been defined. In the following, the objectives and the research activities included in the project are illustrated in detai

ISSN:1124-318X    

DOI:10.1002/ett.4460020205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractThe paper presents the research topics of the «Progetto Finalizzato Telecomunicazio‐ni» partially founded by CNR (National Council for Research) on the multi‐media terminals, video broadcast terminal and HDTV (High Definition Television) signal processing. It describes the main features of a full ATM Workstation, of ISDN multiservice terminal and digital video broadcast codec connected to ATM node. It presents also the studies on HDTV by simulation of algo

ISSN:1124-318X    

DOI:10.1002/ett.4460020206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractThe objectives and the early technical results of a project for the realization of an ATM local network testbed are described. The aim of the project is to realize a flexible experimentation environment to investigate the critical issues related to the introduction of ATM techniques in the network, including signalling, interworking and service support, in addition to the basic switching technology. After presenting the general structure and the solutions adopted for the testbed, the paper describes the main characteristics of its building blocks currently under development: the switching node with its ATM switching fabric and control units, the access network with the related interfaces and protocols, the customer equipment composed by ATM workstations, ATM terminal adaptors and LAN gateways, the interworking unit connecting the testbed to the telephone network. Finally the resources allocation and policing functions adopted are also discussed.

ISSN:1124-318X    

DOI:10.1002/ett.4460020207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractThe advantages of broadband communication networks are outlined. The activities developed in the framework of the Sub‐Project 5 of the C.N.R. Telecommunications Project are presented: the study and implementation of LANs and MANs using different communication links (optical fibres, satellite systems and also, for urban areas, microwave systems); the study of high speed optical communication networks (deflection networks and multi‐hop networks); the experiments on advanced services, carried out mainly for the scientific users. Two services are in particular outlined, teleeducation and telemedicine, on which experiments are planned with the aim of exploiting the capabilities of the broadband communication networks. Some indications are also given on the geographical areas, that are candidate for LANs‐MANs implementation and experiments perfor

ISSN:1124-318X    

DOI:10.1002/ett.4460020208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractThe paper aims at describing a possible evolution strategy of a telecommunication network architecture which should provide users with a wide range of broadband services in a relatively short term. The discussion reflects the work carried out within the Italian «Progetto Finalizzato Telecomunicazioni» and it assumes, as starting points, the deployment of a digital network structure, together with the first introduction of the new Synchronous Digital Hierarchy (SDH) equipment.On the basis of the mentioned hypotheses, the exploitation in the network of the SDH capabilities, the role of Metropolitan Area Networks (MANs) and the issues related to the deployment of optical fibres in the distribution network are discussed with the target to provide a «grace‐ful» evolution path towards the future ATM‐based Broadband ISDN (

ISSN:1124-318X    

DOI:10.1002/ett.4460020209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractThe paper, after a general survey of Metropolitan Area Network (MAN) issues, in which the market demand and recent trends in MAN concepts (e.g. relationship with Broadband Integrated Services Digital Network, B‐ISDN) are considered, examines the ongoing MAN related activities inside standard‐setting bodies such as IEEE (Institute of Electrical and Electronic Engineers) and ETSI (European Telecommunications Standards Institute). Emerging trends in architecture, protocols and services are reviewed.A more detailed characterization of the bearer services MANs are required to provide (i.e. connectionless, non isochronous connection oriented and isochronous) is then given, emphasizing their broadband nature and the related applications; the functions providing these services within the Distributed Queue Dual Bus (DQDB) framework are briefly described.The last section is devoted to a discussion of MAN performance. specifically in terms of fairness, focusing again on the DQDB protocol, which appears to be the most promising solution for MANs, and on possible improvements of its characterist

ISSN:1124-318X    

DOI:10.1002/ett.4460020210

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractThe perspectives for digital HDTV on satellite channels are examined at the light of the recent progress on bit‐rate reduction algorithms and on modulation and channel coding techniques. The experimental HDTV transmissions at 70 Mbit/s carried out by the RAI during the «1990 Football Worldcup» are shortly described. A preliminary configuration of the future HDTV network architecture has been identified, including terrestrial and satellite links. Two advanced modulation and coding systems, suitable for operating in the 30/20 GHz frequency range, have been studied by computer simulations: a) QPSK modulation and concatenated convolutional and Reed‐Solomon coding, and b) Trellis‐coded 8‐PSK modulation and concatenated Reed‐Solomon coding. The satellite channel has been optimized as regards the transmitting and receiving filters partitioning and the TWTA operating point. An example of design of a complete satellite chain at 30/20 GHz shows the feasibility of a 140 Mbit/s HDTV transmission system based on the described

ISSN:1124-318X    

DOI:10.1002/ett.4460020211

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY