吥唥靜尐姐
随着手机的普及,新一代移动通信系统的研究正如火如荼地进行中,从1995年问世的第一代(1G)模拟制式手机,到1996到1997年出现的第二代(2G)GSM、TDMA等数字制式手机,在经历了前两代的发展之后第三代(3G)移动通信技术手机,技术已经变得越来越成熟。中国的3G牌照在2009年1月7日正式下发,分别是移动(TD-SCDMA),联通(WCDMA)电信(CDMA2000),标明了中国正式进入3G时代!而3G网络也代表着这一技术的发展方向,而这一技术的研究并不是只言片语可以阐明,而这一技术的研究也显得非常地重要。 本论文完整的介绍了TD-SCDMA,WCDMA,CDMA2000三种不同的3G移动通信国际主流标准,覆盖了3G系统整体架构和相关知识点,对基础原理,无线接口技术,3G网络的特点,以及通信系统双工方式进行了阐述。 关键词:3G,移动通信,无线接口技术,双工方式 With the popularity of mobile phones, next-generation mobile communication system is in the middle of the study carried out in 1995 came from the first generation (1G) analog mobile phone system to the years 1996-1997 the second generation (2G) GSM, TDMA, etc. the number of standard mobile phones, after the first two generations after the development of third generation (3G) mobile communications technology mobile phones, technology has become more and more mature. China's 3G license in January 7, 2009 issued a formal, namely mobile (TD-SCDMA), Unicom (WCDMA) telecommunications (CDMA2000), marked China's formal entry into the 3G era! The 3G network also represents the direction of development of this technology, and this technology is not a word or two can be clarified, and this technology is also very important. This paper describes a complete TD-SCDMA, WCDMA, CDMA2000 three different international mainstream 3G mobile communications standard, covering the overall framework of 3G systems and related knowledge, the basic principle of the wireless interface technology, 3G network characteristics, as well as communication duplex mode system are described. Keywords: 3G, mobile communications, wireless interface technology, duplex mode
黑粉精灵
Although the twentieth Century 90 time metaphase, network community has begun to put the next generation network (NGN) or the next generation of Internet (NGI), but the researches focus on the IPv6 based technology. Until 2005, American global network of innovation environment (GENI) bodies in relevant documents publicly acknowledged that IPv6 failed to resolve the Internet challenge, we must re-examine the existing network system structure. So far, research on issues related to network architecture that has attracted wide attention from the academia and the industry at home and abroad, put forward many NGI/NGN architecture. Communication network is increasingly huge, advanced and complex, so it is difficult to describe the network structure with a structure chart, and according to the application demand of network architecture from more than one side design. Aiming at a series of challenges to deal with Internet, introduces a new network architecture: hierarchical switching network technology. With this technology, completely lost to the network router; regression simple; let the path packets can be predicted, the reasonable application of network channel resources; failure to change, the topology of the network, network equipment and communication lines and recovery, network management personnel misoperation incidents localization; let fast self-healing ability does not depend on another set of complex networks (such as SDH/SONET); let the multicast tree formed naturally; let the backbone network address space and the user address space separation of user behavior is easy to track. At the same time with the progress of related research situation at home and abroad, further analysis of the characteristics of the hierarchical network architecture, and builds a typical hierarchical network using Packet 。Tracer, to show the remarkable superiority.
润风水尚
Although the mid -1990s , the network industry has begun to raise the next generation network (NGN) or the next generation Internet (NGI), but focused on the research focus to IPv6 -based technologies. Until 2005 , the . Global Network Innovation Environment (GENI) institutions in the relevant documents publicly acknowledged IPv6 failed to solve the challenges facing the Internet , you must re-examine the existing network architecture. So far, the research questions about the network architecture was attracted wide attention in academia and industry , domestic and presented numerous NGI / NGN architecture. Growing communication network of giant , Advancement and complex, making it difficult to depict the structure of a network structure , and the needs of the network architecture should be applied from the plurality of side design . In this paper, a series of challenges to deal with the current Internet is difficult to introduce a new network architecture : hierarchical switching network technology. With this technique, completely lost router ; let network regression concise ; let the packet path predictable network channel resources to obtain reasonable application ; make changes in the network topology information , failure and recovery network equipment and communication lines , network management personnel localized incidents of misuse ; allow rapid healing ability is not dependent on another set of complex networks ( such as SDH / SONET); allow multicast tree formed naturally ; let backbone network address space separate from the user address space ; user bad behavior is easy to trace . Combined with domestic and foreign research progress of work -related cases, further analysis of hierarchical network architecture features and using Packet Tracer construct a typical hierarchical network , to demonstrate its significant advantages.
仿佛那一天
随着手机的普及,新一代移动通信系统的研究正如火如荼地进行中,从1995年问世的第一代(1G)模拟制式手机,到1996到1997年出现的第二代(2G)GSM、TDMA等数字制式手机,在经历了前两代的发展之后第三代(3G)移动通信技术手机,技术已经变得越来越成熟。中国的3G牌照在2009年1月7日正式下发,分别是移动(TD-SCDMA),联通(WCDMA)电信(CDMA2000),标明了中国正式进入3G时代!而3G网络也代表着这一技术的发展方向,而这一技术的研究并不是只言片语可以阐明,而这一技术的研究也显得非常地重要。 Along with handset's popularization, the new generation mobile communication system's research like a raging fire is being carried on, was published the first generation of (1G) simulation service pattern handset from 1995, to 1996 second generation of digital service pattern handsets and so on (2G)GSM which, TDMA to 1997 appeared, after having experienced the first two generation of development the third generation (3G) mobile communication technology handset, the technology already became more and more mature. China's 3G license plate after-crops officially in January 7, 2009, respectively is moves (TD-SCDMA), the link (WCDMA) telecommunication (CDMA2000), marked China to enter the 3G time officially! But the 3G network is also representing this technical development direction, but this technology's research is not the word may expound, but this technology's research also appears very important. 论文完整的介绍了TD-SCDMA,WCDMA,CDMA2000三种不同的3G移动通信国际主流标准,覆盖了3G系统整体架构和相关知识点,对基础原理,无线接口技术,3G网络的特点,以及通信系统双工方式进行了阐述。 The paper complete introduction TD-SCDMA, WCDMA, CDMA2000SAN kind of different 3G mobile communication international mainstream standard, has covered the 3G system overall construction and the related knowledge spot, to the foundation principle, the wireless connection technology, the 3G network's characteristic, as well as the communications system duplex mode has carried on the elaboration.
Mr.白马王爷
Abstract With the popularity of mobile phones, next-generation mobile communication system is in the middle of the study carried out in 1995 came from the first generation (1G) analog mobile phone system to the years 1996-1997 the second generation (2G) GSM, TDMA, etc. the number of standard mobile phones, after the first two generations after the development of third generation (3G) mobile communications technology mobile phones, technology has become more and more mature. China's 3G license in January 7, 2009 issued a formal, namely mobile (TD-SCDMA), Unicom (WCDMA) telecommunications (CDMA2000), marked China's formal entry into the 3G era! The 3G network also represents the direction of development of this technology, and this technology is not a word or two can be clarified, and this technology is also very important. This paper describes a complete TD-SCDMA, WCDMA, CDMA2000 three different international mainstream 3G mobile communications standard, covering the overall framework of 3G systems and related knowledge, the basic principle of the wireless interface technology, 3G network characteristics, as well as communication duplex mode system are described. Keywords: 3G, mobile communications, wireless interface technology, duplex mode
蓝牙技术允许信息存储在手机上可以显示在电视上,也可以变换分析的信息,以便在电脑上听声。 蓝牙技术的传输速率设计到1MHz。实现全双工通信的时间division
分类: 教育/科学 >> 学习帮助 问题描述: 我订阅了如 "TIME(时代周刊)" 等英文杂志,想看到整版内容相同的全中文版. 解析:
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