ITU-T G.631-1988 线路频率约低于是45M Hz的系统所用海底电缆的各类型 Types of submarine cable to be used for systems with line frequencies of less than about 45 MHz

pdf标准 ITU-T G.631-1988 线路频率约低于是45M Hz的系统所用海底电缆的各类型 Types of submarine cable to be used for systems with line frequencies of less than about 45 MHz

3 页 0 下载 1 浏览 0 评论 0 收藏 3.0分
温馨提示:当前标准最多只能预览 10 页,若标准超出了 10 页,请下载原标准以浏览全部内容。
ITU-T G.631-1988 线路频率约低于是45M Hz的系统所用海底电缆的各类型 Types of submarine cable to be used for systems with line frequencies of less than about 45 MHz  第 1 页 ITU-T G.631-1988 线路频率约低于是45M Hz的系统所用海底电缆的各类型 Types of submarine cable to be used for systems with line frequencies of less than about 45 MHz  第 2 页 ITU-T G.631-1988 线路频率约低于是45M Hz的系统所用海底电缆的各类型 Types of submarine cable to be used for systems with line frequencies of less than about 45 MHz  第 3 页
本标准由 5zbz2018-09-16 14:48:14上传分享

国外分类,ITU,ITU-T(电信标准分局),itu,线路,频率,低于,45m,hz,系统,所用,海底,电缆,类型,types,of,submarine,cable,to,be,used,for,systems,with,line,frequencies,of,less,than,about,mhz

INTERNATIONAL TELECOMMUNICATION UNION )45 4 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU 42!.3-)33)/. -%$)! #(!2!#4%2)34)#3 490%3 /& 35"-!2).% #!",% 4/ "% 53%$ &/2 3934%-3 7)4( ,).% &2%15%.#)%3 /& ,%33 4(!. !"/54  -(Z )45 4 Recommendation ' (Extract from the "LUE "OOK) ' NOTES 1 ITU-T Recommendation G.631 was published in Fascicle III.3 of the Blue Book. This file is an extract from the Blue Book. While the presentation and layout of the text might be slightly different from the Blue Book version, the contents of the file are identical to the Blue Book version and copyright conditions remain unchanged (see below). 2 In this Recommendation, the expression “Administration” is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. © ITU 1988, 1993 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the ITU. Recommendation G.631 Fascicle III.3 - Rec. G.631 TYPES OF SUBMARINE CABLE TO BE USED FOR SYSTEMS WITH LINE FREQUENCIES OF LESS THAN ABOUT 45 MHz (Geneva, 1976) The CCITT, recognizing that the special complications of cable repair in the case of submarine cable systems laid in deep water (i.e. at depths where there is no need to use armoured cables) justify measures which would reduce the number of cable types with which repair ships have to deal; appreciating at the same time that system designers require flexibility in the choice of cables in order to optimize the overall cost per unit length of individual systems; recognizing that the most significant cable characteristics in determining whether any two cables may be joined together are: - the inner diameter of the outer conductor, - the characteristic impedance of the cable, recommends that for submarine systems handling line frequencies up to 45 MHz the cable used in the deep water sections of such systems should conform with the limits set out in Table 1/G.631. TABLE 1/G.631 Inner diameter of outer conductor Characteristic impedance 25.0-25.5 mm 37.0-38.5 mm 43.2 mm 43-46 Ω a) 53-54 Ω a) 49-50 Ω b) 60-62 Ω b) 53-54 Ω c) 60-62 Ω Fascicle III.3 - Rec. G.631 1

给标准打分
您好可以输入 255 个字符
本站的中文名字叫什么( 答案:找标准 )
评论列表
  • 暂时还没有评论,期待您的金玉良言