1,866 research outputs found

    A review of personal communications services

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    This article can be accessed from the link below - Copyright @ 2009 Nova Science Publishers, LtdPCS is an acronym for Personal Communications Service. PCS has two layers of meaning. At the low layer, from the technical perspective, PCS is a 2G mobile communication technology operating at the 1900 MHz frequency range. At the upper layer, PCS is often used as an umbrella term that includes various wireless access and personal mobility services with the ultimate goal of enabling users to freely communicate with anyone at anytime and anywhere according to their demand. Ubiquitous PCS can be implemented by integrating the wireless and wireline systems on the basis of intelligent network (IN), which provides network functions of terminal and personal mobility. In this chapter, we focus on various aspects of PCS except location management. First we describe the motivation and technological evolution for personal communications. Then we introduce three key issues related to PCS: spectrum allocation, mobility, and standardization efforts. Since PCS involves several different communication technologies, we introduce its heterogeneous and distributed system architecture. IN is also described in detail because it plays a critical role in the development of PCS. Finally, we introduce the application of PCS and its deployment status since the mid-term of 1990’s.This work was supported in part by the National Natural Science Foundation of China under Grant No. 60673159 and 70671020; the National High-Tech Research and Development Plan of China under Grant No. 2006AA01Z214, and the Engineering and Physical Sciences Research Council (EPSRC) of UK under Grant EP/E060722/1

    An investigation into advance time division multiple access based personal communication networks : this thesis is presented in partial fulfilment of the requirements for the degree of Master of Technology in Production Technology at Massey University

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    This thesis examines and simulates a statistically multiplexed multiple access technique known as Advanced Time Division Multiple Access (ATDMA). The simulations were carried out in a multimedia traffic environment. Parameters that could optimise the network performance in terms of quality, reliability and capacity have been examined using a simulation model. This thesis also examines network architecture and signalling related issues. The simulation results were analysed to propose a suitable ATDMA frame structure in terms of the frame length and the organisation of traffic and reservation slots. The simulation results indicated that the performance of the ATDMA based system can be enhanced when delay insensitive data is transmitted as blocks of packets of a specific size. The simulation results also indicated that the performance of the ATDMA based system can be further enhanced when a video terminal is allocated a single traffic slot as opposed to multiple traffic slots. Further simulations have been carried out to determine the up-link traffic channel capacities and control channel capacities. This thesis also examined aspects that could further enhance the performance of an ATDMA based system

    Deregulation and Enterprization in Central and Eastern Telecommunication - a Benchmark for the West?

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    The restructuring of telecommunication in Central and Eastern Europe occurs at a time when the classical structures of telecommunication are falling apart worldwide. Coming from the socialist system in which telecommunication did not exist as an independent economic activity, the Eastern European countries have created specific "post-socialist" modes of reform, often outdoing Western countries in terms of speed and radicality. Deregulation and enterprization have dominated the process in all countries, leading to advanced technical standards and a wide segmentation of telecommunication markets. The role of foreign direct investment and technology transfer was particularly important. But the reforms also lead to an increasing social gap between the prosperous users of advanced telecommunication services, and the average citizen for which even telephony has become a luxury good. Our thesis is that CEE telecommunication reform, rather than copying Western models, may become a benchmark for the West, in particular for Western Europe. Technically, the advanced reform countries in Central Europe are about to succeed the leapfrogging process, i.e. the jump from post-war socialist technologies to world-leading edge-of-technology standards. With regard to industry structures, Central and Eastern European countries show that the age of "classical" integrated telecommunication activities is definitely over. Instead, most diversified telecommunication services are integrated in the emerging information sector. Finally, the very notion of telecommunication as an "infrastructure" is put in question for the first time in Eastern Europe. We start to address the two relevant policy issues: modes of regulation, and science and technology policies to accompany the restructuring process.

    Broadband: Europe needs more than DSL

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    Efficient broadband technologies such as DSL, fibre, cable modem, powerline communications, UMTS, WLAN or WiMax are powerful locational factors for an economy. Europe in particular should promote broadband communication further to tap into its growth potential. But given the prevailing ownership structures in fixed wire business, the promotion of broadband must not concentrate exclusively on DSL. Rather, its impact should be technology-neutral.communications, technology, broadband, DSL, cable modem, FTTH, regulation authority, liberalisation, deregulation, convergence

    Mobile telephony - cooperation and value-added are key to further success

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    The current problems in mobile telephony are leading critics to make overly pessimistic predictions that 3G – the third-generation mobile phone system – will never become profitable. However, the resulting calls not to introduce 3G and instead directly back alternative wireless technologies (e.g. WLAN) are a step too far. Ultimately, a profit- oriented service can only create significant value-added with a mix of both 3G and WLAN technologies. It is notable that no attractive broadband-dependent applications have emerged as yet. The typical user is only interested in the value-added the application provides, not the underlying wireless technology. Although mobile telephony remains one of the most dynamic areas of the economy, euphoria is misplaced. Advanced wireless technologies will on no account become profitable before the start of the next decade. But even that is not a given; this will challenge the entrepreneurial spirit of network operators, mobile terminal manufacturers and service providers alike.ICT, IT, mobile, telephony, UMTS, WLAN

    The coherence of EU trade, competition, and industry policies in the high tech sector : the case of the telecommunications services sector

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    We analyze the coherence existing among European Union competition, industry, and trade policies in the high tech sector in general terms focusing on its specific features (externalities, fast progress) and their effects on the emergence and treatment of policy consistency and conflicts. Second, this analysis is applied to the European telecommunications services sector. The examination of this sector and the relevant EU policies reveals a consensus on giving priority to competition. However structural factors prevent policy implementation to reflect much liberalization and harmonization and business responses to trade globalization challenge effective competition. The potential, important role of standardization is shown.economics of technology ;

    STUDI INTEGRASI JARINGAN MULTIMEDIA B-ISDN/ATM DENGAN UMTS (Universal Mobile Telecommunication System)

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    Perkembangan implementasi dari komunikasi multimedia mengarah pada struktur jaringan kabel yang sudah ada, namun tidak memungkinkan untuk dapat dipakai di sembarang tempat karena ketiadaan perangkat yang portable. UMTS sebagai sistem telekomunikasi generasi ketiga dipersiapkan untuk dapat mendukung komunikasi data dan multimedia serta dapat mendukung bermacam-macam layanan yang ditawarkan oleh jaringan tetap yang ada saat ini termasuk dengan jaringan B-ISDN. UMTS mempertimbangkan layanan laju data radio sebesar 144 Kbps sampai 2 Mbps untuk mendukung berbagai macam layanan data multimedia dimana jenis dari akses radio tersebut akan menjangkau dari sambungan dengan laju bit yang konstan maupun yang variabel, akses paket yang berorientasi koneksi sampai akses paket yang tak terkoneksi pada band frekuensi 2 GHz. Integrasi yang dilakukan menggunakan fasilitas infrastruktur jaringan yang sudah ada yang berbasiskan pada ATM transport dan integrasi dengan konsep IN serta mendukung pemakaian antarmuka radio serta mengadopsi IP (Internet Protocol) switching dan aplikasi protokol yang dapat digunakan untuk interaksi antara entitas yang menyilang dari antarmuka yang digunakan untuk aplikasi protokol manajemen UMTS adalah bebas, antara lain SNMP, CNIP dan CORBA. Dengan mobilitas, laju bit dan band frekuensi yang besar serta fleksibilitas yang dipunyai UMTS maka proses integrasi dengan jaringan multimedia B-ISDN/ATM dapat dimungkinkan dengan kualitas layanan yang identik dengan jaringan yang sudah ada

    WCDMA in Malaysia

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    Wideband Code Division Multiple Access (WCDMA) A 3G highspeed digital data service provided by cellular carriers that use the time division multiplexing (TDMA) or GSM technology worldwide, including AT&T (formerly Cingular) and T-Mobile in the U.S. WCDMA works on WCDMA cell phones as well as laptops and portable devices with WCDMA modems [1]. Users have typically experienced downstream data rates up to 400 Kbps [1]. WCDMA has been used in the Japanese Freedom of Mobile Multimedia Access (FOMA) system and in the Universal Mobile Telecommunications System (UMTS); a third generation follow-on to the 2G GSM networks deployed worldwide [1]. Although TDMA and GSM carriers both use TDMA modulation, WCDMA stems from CDMA. Part of the 3GPP initiative, the International Telecommunication Union (ITU) refers to WCDMA as the Direct Sequence (DS) interface within the IMT-2000 global 3G standards [1]

    Information and communication technologies in Germany : Is there a remaining role for sector-specific regulation?

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    In order to analyze the remaining role for sector-specific regulation the focus of this paper is on those elements of the Internet periphery and Internet service provision, which are strongly based on telecommunications, in particular Internet access and Internet backbone. Section 2 deals with the role of telecommunications for the Internet, differentiating between local network access and long distance network capacity. In section 3 the new regulatory arrangements for communications services within Europe, with particular emphasis on Germany, are explained. In order to analyze the future role of sector-specific regulation from a normative point of view, in section 4 the network economic concept of a disaggregated regulatory approach is provided. Section 5 deals with phasing-out potentials for sector-specific regulation due to increasing competition within the local loop. In section 6 the role of technology-neutral regulation is considered, which implies that in an environment of competing network infrastructures sector- specific regulation should not be extended, but removed. Finally, section 7 explains the role of competition in the markets for backbone interconnectivity. --

    More than 'pretend competition' in German telecommunications

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    In a globally networked economy, the telecommunications sector – which was long in the hands of a state-run company – must not close its eyes to competition. All the same, Germany was late in starting to deregulate the industry and so far has concentrated more on competition among service providers than among network operators. Even though several steps have been taken to open the telecommunications market further, the former monopolist continues to dominate it so strongly that critics speak of mere 'pretend' competition.ICT, fixed line, telephony, regulation
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