ITU-T G 411-1993 USE OF RADIO - RELAY SYSTEMS FOR INTERNATIONAL TELEPHONE CIRCUITS《国际电话电路中无线接力系统的应用》.pdf

1、INTERNATIONAL TELECOMMUNICATION UNION)45G134 TELECOMMUNICATIONSTANDARDIZATION SECTOROF ITU).4%2.!4)/.!,G0G0!.!,/5%G0G0#!22)%2G0G03934%-3%.%2!,G0G0#(!2!#4%2)34)#3G0G0/&G0G0).4%2.!4)/.!,#!22)%2G0G04%,%0(/.%G0G03934%-3G0G0/.2!$)/G0G13G02%,!9G0G0/2G0G03!4%,)4%G0G0,).+3G0G0!.$).4%2#/%#4)/.G07)4(G0G0-%4!,

2、)#G0G0,).%353%G0G0/&G0G02!$)/G0G13G02%,!9G0G03934%-3G0G0&/2).4%2.!4)/.!,G0G04%,%0(/.%G0G0#)2#5)43)45G134G0G0RecommendationG0G0 (Extract from the “LUEG0“OOK)NOTES1 ITU-T Recommendation G.411 was published in Fascicle III.2 of the Blue Book. This file is an extract fromthe Blue Book. While the present

3、ation and layout of the text might be slightly different from the Blue Book version, thecontents 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

4、 atelecommunication administration and a recognized operating agency. ITU 1988, 1993All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic ormechanical, including photocopying and microfilm, without permission in writing from the ITU.Fa

5、scicle III.2 - Rec. G.411 1Recommendation G.411Fascicle III.2 - Rec. G.411USE OF RADIO-RELAY SYSTEMS FOR INTERNATIONALTELEPHONE CIRCUITSThe CCITTunanimously recommends1)that, between fixed points, telephone communications should be effected wherever possible by means ofmetallic conductors or radio-r

6、elay links using frequencies above 30 MHz to make the allocation of radio-frequencies lessdifficult and, where this can be realized, the objective should be to attain the transmission performance recommended bythe CCITT for international telephone circuits on metallic conductors.Reference1 CCIR Recommendation Use of radio links in international telephone circuits, Vol. III, Rec. 335, Dubrovnik, 1986._1)This Recommendation is the same as an extract from CCIR Recommendation 335 1.