ITU-T G 991 2-2003 Single-pair high-speed digital subscriber line (SHDSL) transceivers (Study Group 15)《单线对高速数字用户线(SHDSL)收发信机-修正1》.pdf
《ITU-T G 991 2-2003 Single-pair high-speed digital subscriber line (SHDSL) transceivers (Study Group 15)《单线对高速数字用户线(SHDSL)收发信机-修正1》.pdf》由会员分享,可在线阅读,更多相关《ITU-T G 991 2-2003 Single-pair high-speed digital subscriber line (SHDSL) transceivers (Study Group 15)《单线对高速数字用户线(SHDSL)收发信机-修正1》.pdf(234页珍藏版)》请在麦多课文档分享上搜索。
1、 INTERNATIONAL TELECOMMUNICATION UNION ITU-T G.991.2TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (12/2003) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Digital sections and digital line system Access networks Single-pair high-speed digital subscriber line (SHDSL) transce
2、ivers ITU-T Recommendation G.991.2 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS INTERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITS G.100G.199 GENERAL CHARACTERISTICS COMMON TO ALL ANALOGUE CARRIER-TRANSMISSION SYSTEMS G.200G.299 INDIVIDUAL CHARACTERISTICS
3、 OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON METALLIC LINES G.300G.399 GENERAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON RADIO-RELAY OR SATELLITE LINKS AND INTERCONNECTION WITH METALLIC LINES G.400G.449 COORDINATION OF RADIOTELEPHONY AND LINE TELEPHONY G.450G.499 TESTING EQUIPM
4、ENTS G.500G.599 TRANSMISSION MEDIA CHARACTERISTICS G.600G.699 DIGITAL TERMINAL EQUIPMENTS G.700G.799 DIGITAL NETWORKS G.800G.899 DIGITAL SECTIONS AND DIGITAL LINE SYSTEM G.900G.999 General G.900G.909 Parameters for optical fibre cable systems G.910G.919 Digital sections at hierarchical bit rates bas
5、ed on a bit rate of 2048 kbit/s G.920G.929 Digital line transmission systems on cable at non-hierarchical bit rates G.930G.939 Digital line systems provided by FDM transmission bearers G.940G.949 Digital line systems G.950G.959 Digital section and digital transmission systems for customer access to
6、ISDN G.960G.969 Optical fibre submarine cable systems G.970G.979 Optical line systems for local and access networks G.980G.989 Access networks G.990G.999 QUALITY OF SERVICE AND PERFORMANCE GENERIC AND USER-RELATED ASPECTS G.1000G.1999 TRANSMISSION MEDIA CHARACTERISTICS G.6000G.6999 DIGITAL TERMINAL
7、EQUIPMENTS G.7000G.7999 DIGITAL NETWORKS G.8000G.8999 For further details, please refer to the list of ITU-T Recommendations. ITU-T Rec. G.991.2 (12/2003) i ITU-T Recommendation G.991.2 Single-pair high-speed digital subscriber line (SHDSL) transceivers Summary This Recommendation describes a transm
8、ission method for data transport in telecommunications access networks. SHDSL transceivers are designed primarily for duplex operation over mixed gauge two-wire twisted metallic pairs. Optional multi-pair operation is supported for extended reach applications. Optional signal regenerators for both s
9、ingle-pair and multi-pair operation are specified, as well. SHDSL transceivers are capable of supporting selected symmetric user data rates in the range of 192 kbit/s to 2312 kbit/s using a Trellis Coded Pulse Amplitude Modulation (TCPAM) line code. Optional extensions described in Annex F allow use
10、r data rates up to 5696 kbit/s. SHDSL transceivers are designed to be spectrally compatible with other transmission technologies deployed in the access network, including other DSL technologies. SHDSL transceivers do not support the use of analogue splitting technology for coexistence with either PO
11、TS or ISDN. Regional requirements, including both operational differences and performance requirements, are specified in Annexes A, B and C. Requirements for signal regenerators are specified in Annex D. Annex E describes application-specific framing modes that may be supported by SHDSL transceivers
12、. See Annex H/G.992.1 1 for specifications of transceivers for use in networks with existing TCM-ISDN service (as specified in Appendix III/G.961, in Bibliography B1). History With respect to the previous version 1 (2001), this version 2 introduces the following additions and modifications: The opti
13、onal four-wire mode has been extended to a more general multi-pair mode which provides optional support for up to four-pair connections. See 7.2.1.5. Note that the integrity of the optional 4-wire mode in revision 1 is preserved. The four-wire mode is identical to M-pair mode with M = 2, except for
14、the method of assigning ordinal numbers to the wire pairs. In four-wire mode, the ordinal numbers (the wire pair identification number) are assigned as described in 6.3, while in M-pair mode the ordinal numbers are assigned to wire pairs as described in 7.2.1.5. The loops and test conditions specifi
15、ed in Annex B have been updated (see B.3.3), and Appendix IV, Tabulation of Annex B Noise Profiles, has been added. Optional extensions, described in Annex F, allow user data rates up to 5696 kbit/s. Deactivation and warm-start, as specified in Annex H, have been added. Support for Dynamic Rate Repa
16、rtitioning has been added to Dual-Bearer mode. See E.10.3. TPS-TC definitions have been added for Packet Transfer Mode (E.11), Synchronous Transfer Mode with a Dedicated Signalling Channel (E.12), and V5 Encapsulated ISDN or POTS (E.13). Source ITU-T Recommendation G.991.2 was approved on 14 Decembe
17、r 2003 by ITU-T Study Group 15 (2001-2004) under the ITU-T Recommendation A.8 procedure. ii ITU-T Rec. G.991.2 (12/2003) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications. The ITU Telecommunication Standardization Sec
18、tor (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets ever
19、y four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview
20、, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is volunta
21、ry. However, the Recommendation may contain certain mandatory provisions (to ensure e.g. interoperability or applicability) and compliance with the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the ne
22、gative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the
23、 use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendat
24、ion, ITU had received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementors are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database. ITU 2004 Al
- 1.请仔细阅读文档,确保文档完整性,对于不预览、不比对内容而直接下载带来的问题本站不予受理。
- 2.下载的文档,不会出现我们的网址水印。
- 3、该文档所得收入(下载+内容+预览)归上传者、原创作者;如果您是本文档原作者,请点此认领!既往收益都归您。
下载文档到电脑,查找使用更方便
10000 积分 0人已下载
下载 | 加入VIP,交流精品资源 |
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- ITUTG99122003SINGLEPAIRHIGHSPEEDDIGITALSUBSCRIBERLINESHDSLTRANSCEIVERSSTUDYGROUP15 单线 高速 数字 用户 SHDSL

链接地址:http://www.mydoc123.com/p-797235.html