Có 20+ tài liệu thuộc chủ đề "GMS"
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Thông tin di động ngày nay đã trở thành một dịch vụ kinh doanh không thể thiếu được của tất cả các nhà khai thác viễn thông trên thế giới. Đối với các khách hàng viễn thông, nhất là các nhà doanh nghiệp thì thông tin di động trở thành phương tiện liên lạc quen thuộc và không thể thiếu...
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Chương II Hệ thống thông tin di động GSM. Hoàng Anh Dũng 17 Điện tử 3 K47. AGCH (Access Grant Channel): Kênh cho phép truy nhập AGCH, là kênh hướng xuống, mang tin tức phúc đáp của BTS đối với bản tin yêu cầu kênh của MS để thực hiện một kênh lưu lượng TCH và kênh DCCH cho thuê...
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Chapter 1: GSM’s Achievements. 1.1.1 Introduction to the Content of the Book. This book describes how global mobile communication was made. Young professionals who want to build their career on GSM and UMTS and need to understand the basics. Strategic and technical planners who want to drive the future GSM and UMTS develop- ment. Strategists who plan to repeat GSM’s...
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Parameters of the GSM Standard (mid-1982 to mid-1987). That system would have been unable to fulfil many of the requirements now placed on the GSM system.. The essential contents of the Basic Requirements in the Study Plan of 1982 are given below.. High spectrum efficiency and state-of-the-art subscriber facilities must be achieved.. No significant modification of the fixed national telephone...
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Specification Work Leading to the GSM Phase 1 Standard used for the Opening of Service. Mid-1987 was a milestone in the work of GSM. I think everybody in the group felt, despite what they might have felt earlier, that the agreement on the basic parameters in the air interface marked the turning point in the work. Suffice it to say...
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When the agreement on the selection of the GSM technology had been achieved some people thought that the rest would be easy. We knew however that producing a set of specifications that would ensure the interpretability of mobile stations produced by any mobile terminal manufacturer, and network infrastructure produced by any manufacturer of network infra- structure, or the interoperability of...
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5.1.1.1 The Invention of the Phase 21 Concept. or ‘‘the further work programme. The objective here was to maintain a full internal consistency of the GSM core specifications and test specifications throughout the various stages of their evolution. was a consequence of the progress of microelectronics, as is explained below. There was nothing really revolutionary even if other items were...
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6.1 US Regulatory Status in the 1990s. During the first part of the 1990s, the regulatory climate in the US cellular environment was fashioned by the components of the time. CDMA was thought by some to be the saviour of the world, capacity wise, and others were firmly committed to TDMA and some even to enhancements of TDMA.. A new...
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Chapter 7: The UMTS Related Work of the European. Telecommunications were central to the performance of the services sector and crucial to the business competitiveness. Recognising these trends, European industry ministers 2 , launched a ‘‘Definition Phase’’ of the RACE programme. In the RACE community it was recognised at the time, well before the commercial introduction of GSM, that a...
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8.1.2 The Genesis of the UMTS Concept. This MoU would have defined the conditions of the introduction of UMTS in Europe. In the opening speech Roland Hueber, the head of the RACE office made several agressive statements. In the meantime CEC funded R&D projects continued within the framework of the ACTS programme. In the mid-1980s, even before producing results, the...
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Having read the title, it should not surprise you that this section deals with the creation of the Partnership Project for the standardisation of a Third Generation Mobile Communications System (3GPP).. process undertaken in the middle of the 1990s, we have the fertile soil, i.e. One of the lessons learnt from this exercise was: Why don’t we really co-operate, i.e....
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10.1.3.2 The ‘‘Coexistence Between Vehicle-borne and Hand-held Stations’’. In the end ‘‘the meeting agreed that the GSM mandate (Doc 2/82) clearly states that hand- held stations should be catered for in the system. 10.1.4 The First Concept for Services Agreed in February/March 1985 (GSM#7). 10.1.4.3 The first Agreement on a Concept for Services at GSM#7 (February/March 1985). 10.1.5 The Work...
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11.1 Scope. The decisions that were taken in GSM3/SMG3 were centred on the specification of signalling protocols. 11.2 Architecture. This in turn requires a description of the overall system in terms of entities, such as mobile stations, terminals attached to mobile stations, radio base stations, switches. The analysis and description of a system in terms of entities, of interfaces between...
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We were therefore to design a second generation when the true performances of the first generation were not yet known!. The production of the GSM standard was therefore a truly European effort involving all concerned parties of the industry.. 12.1.3 The Choice of the Multiple Access Scheme. 12.1.3.1 The Selection Process. The results of the Paris trial lead to two...
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They are a secure platform for operator defined services allowing operator differentiation by exploiting the power of the microcomputer in the SIM. 13.2 The Committee. The first meeting of the Subscriber Identity Module Expert Group (SIMEG) was hosted by the Dutch PTT in January 1988. 13.3 The Early Years. The chairman of the first meeting was Ge´rard Mazziotto from France...
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14.1 Overview. The codecs operate either in the GSM full-rate traffic channel at the gross bit rate of 22.8 kbit/s (FR, EFR, AMR-WB), or in the half-rate channel at the gross bit rate of 11.4 kbit/s (HR), or in both (AMR). The HR codec [2] was developed to bring channel capacity savings through operation in the half-rate channel. EFR was...
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Certainly, initially, all involved considered protection of user data from eavesdropping as more important than authentication of the user, though some questioned whether the perceived complexity of introducing encryption over the radio interface was justified.. These criticisms are often made without knowledge of the design goals of GSM security nor the regulatory context in which the designers had to work....
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Section 1: The Early Years from mid-1982 up to the Completion of the First Set of Specifications for Tendering in March 1988. 16.1.1 The Mandate by CEPT and the First Action Plan of 1982. Instead the decision leaves the nature of the GSM open, but requests the study of the interconnection with ISDN.. 1 The views expressed in this section...
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Chapter 17: Testing and Type Approval of the Mobile Stations. In this chapter we aim to explain the principles and evolutions of the testing and type approval of the GSM Mobile Equipment (ME). After having recalled the context at the end of the 1980s (paragraph 17.2), we outline the technical background (paragraph 17.3) and we explain the first step of...
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Alarm handling and fault management: Indications of malfunctions or outages of any network component are transferred back to the O&M system. The O&M technician can then remotely interact with the network component in question and try to repair the problem.. Configuration management: Parameters necessary for network configuration such as frequency plans, next-neighbour relationships or handover algorithms are sent from the...