1、INTERNATIONAL TELECOMMUNICATION UN ION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU E.183 (03/98) SERIES E: OVERALL NETWORK OPERATION, TELEPHONE SERVICE, SERVICE OPERATION AND HUMAN FACTORS Operation, numbering, routing and mobile services - International operation - Tones in national signa
2、lling systems Guiding principles for telephone announcements ITU-T Recommendation EA83 (Previously CCITT Recommendation) ITU-T E-SERIES RECOMMENDATIONS OVERALL NETWORK OPERATION, TELEPHONE SERVICE, SERVICE OPERATION AND HUMAN FACTORS OPERATION, NUMBERING, ROUTING AND MOBILE SERVICES INTERNATIONAL OP
3、ERATION Definitions General provisions concerning Administrations General provisions concerning users Operation of international telephone services Numbering plan of the international telephone service E. 100-E. 103 E. 104E. 1 19 E. 120-E. 139 E.140-E.159 E. 160-E. 169 Maritime mobile service and pu
4、blic land mobile service E.200-E.229 OPERATIONAL PROVISIONS RELATING TO CHARGING AND ACCOUNTING IN THE INTERNATIONAL TELEPHONE SERVICE UTILIZATION OF THE INTERNATIONAL TELEPHONE NETWORK FOR NON- TELEPHONY APPLICATIONS ISDN PROVISIONS CONCERNING USERS E.330-E.399 QUALITY OF SERVICE, NETWORK MANAGEMEN
5、T AND TRAFFIC ENGINEERING “WORK MANAGEMENT TRAFFIC ENGINEERING QUALITY OF TELECOMMUNICATION SERVICES: CONCEPTS, MODELS, OBJECTIVES AND DEPENDABILITY PLANNING li For further details, please refer to ITU-T List of Recommendations. - STD=ITU-T RECMN E-383-ENGL 3998 4862593 Ob48683 735 ITU-T RECOMMENDAT
6、ION E.183 GUIDING PRINCIPLES FOR TELEPHONE ANNOUNCEMENTS Summary This Recommendation presents some guidance on the content and timing of announcements used in telephone services. Source ITU-T Recommendation E. 183 was revised by ITU-T Study Group 2 (1 997-2000) and was approved under the WTSC Resolu
7、tion No. 1 procedure on the 9th of March 1998. Recommendation E.183 (03/98) 1 FOREWORD IT (International Telecommunication Union) is the United Nations Specialized Agency in the field of telecommuni- cations. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of the ITU. T
8、he 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 Conference (WTSC), which meets every four years, establishes the topics
9、 for study by the ITU-T Study Groups which, in their turn, produce Recommendations on these topics. The approval of Recommendations by the Members of the ITU-T is covered by the procedure laid down in WTSC Resolution No. 1. In some areas of information technology which fall within IT-Ts purview, the
10、 necessary standards are prepared on a collaborative basis with IS0 and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. INTELLECTUAL PROPERTY RIGHTS The ITU draws attentio
11、n to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. The IT takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by 1I“U members or other
12、s outside of the Recommendation development process. As of the date of approval of this Recommendation, the IT had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementors are cautioned that this may not represe
13、nt the latest information and are therefore strongly urged to consult the TSB patent database. O ITU 1998 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
14、writing &om the IT. 11 Recommendation E.183 (03198) 7 8 . STDmITU-T RECMN E.383-ENGL 1998 4862593 Ob48685 508 CONTENTS Introduction Content of announcements . Timing of announcements Speech quality Tones after announcements Concatenated-word announcements . 6.1 Fluency problems 6.2 Intonation proble
15、ms 6.3 Presentation of numerical information 6.4 Update problems . Tones and announcements for use in telephone services . Preferred listening levels for announcements Recommendation E.183 (03198) Page 1 1 1 2 2 2 2 2 3 3 3 3 . 111 Recommendation E.183 GUIDING PRINCIPLES FOR TELEPHONE ANNOUNCEMENTS
16、(revised in 1998) 1 Introduction Recorded announcements are of great value in the setting up of a call or supplementary service. Administrations will need to use an announcement system which makes the announcements in real time and which permits the inclusion of specific information relating to a pa
17、rticular call or situation. This can be done by storing words or parts of words which can be appropriately assembled to make up the required announcements. These are called “concatenated-word“ announcements. Another approach is to use truly synthetic speech (synthesis-by-rule), generated in real tim
18、e, to produce announcements as required, This avoids the need to store representations of utterances by a natural speaker, and has the advantage of total flexibility in the announcement that can be produced. 2 Content of announcements 2.1 Announcements should not commence with a significant word. 2.
19、2 purposes a maximum of three is recommended. Ideally only one piece of information should be conveyed in an instructional announcement, but for practical 2.3 Repetition of important items of information is advisable. Announcements such as acknowledgement messages and error messages should be produc
20、ed twice. However, guidance announcements which ask for input from the user should normally be produced only once. 2.4 Announcements should be phrased in a polite manner. 2.5 Announcements should be concise. This requirement is especially important for guidance announcements. 2.6 In many languages,
21、simple affirmative sentences are most easily understood and should be used where possible, rather than negative and passive sentences. The use of negatives can sometimes be helpful, however, when emphasizing a point (e.g. as in “Do not . . .“). 2.7 If applicable, the order in which procedural guidan
22、ce is presented should correspond to the order in which actions are required to be executed (e.g. “Please press the # button and then replace the receiver“, rather than “Before replacing the receiver, please press the # button“). 2.8 receive this message, please press the # button“, rather than “Ple
23、ase press the # button to receive the message“). If an action and its consequence are described, the consequence should be stated first, then the action (e.g. “To 2.9 2.10 Jargon should be avoided. Where necessary, announcements should be given in more than one language. 2.11 down, etc.), one should
24、 be selected and used throughout. When several words or phrases could be used to convey the same idea (e.g. handsetkeceiver, hang-uphlear- 3 Timing of announcements 3.1 3.2 language is 150 to 200 words or 300 to 500 syllables per minute. Announcements should start at the beginning for each customer
25、receiving them. The speech rate should not exceed normal conversation speed. For example, normal speech rate for the English Recommendation E.183 (03/98) 1 STD-ITU-T RECMN E-383-ENGL 3998 W 4862593 0648687 380 m 3.3 digest items of information. Attention should be given to the distribution of pauses
26、 within announcements, in order to allow listeners to 3.4 If an announcement is repeated once, the pause between the original announcement and its repetition should be about 2 seconds. Where announcements are required to be repeated more than once, the pause between announcements may be extended (fo
27、r instance 5 to 10 seconds). 3.5 down is recommended (for instance 500 to 1000 msec within a digit sequence). The use of pauses within telephone numbers or items of information that have to be remembered or written Telephone numbers should be grouped with groups of two to four digits according to th
28、e custom. 4 Speech quality 4.1 continue when they have finished. Announcements should not sound as if they have finished when they have not, nor should they sound as if they 4.2 The speech quality of announcements should be assessed by listeners subjective judgements from the users end. The quality
29、should refer to the whole system, including effects of transmission. A measuring method that can be used is the listening opinion test described in Volume V, Supplement 2. 5 Tones after announcements 5.1 some cases dial tone will be appropriate). After guidance announcements which ask for input fi-o
30、m the user, an indication to proceed should be given (in 5.2 When the user is required to replace the receiver following an announcement, congestion tone may be used. 6 Concatenated-word announcements Problems which are peculiar to concatenated-word speech are described in the following subclauses:
31、6.1 Fluency problems The fluency of an announcement is influenced by the duration of the stored speech segment (for instance 1/16 second), and by the location of words within a segment or segments. Fluency may also be influenced by the insertion of additional silent segments between segments of spee
32、ch. An iterative procedure of vocabulary editing and listening to the results until it is judged acceptable is recommended. Human factor tests need to be included in the iterative procedure. Experiments should be held with the typical users. 6.2 Intonation problems Problems arise because speech is r
33、equired to sound natural. Ideally only one version of each word would be assembled from segments held in store, as this would be the easiest and cheapest method of providing a range of announcements. However, the intonation pattern of a word may need to vary depending on the position of the word wit
34、hin a sentence. For example: a) “All calls to XXXX are being diverted“. The stress on the word “diverted“ falls towards the end of the word. “Your call to Dr. Smith is being “diverted“ to Dr. Jones“. The pitch of the word “diverted“ is neutral. b) 2 Recommendation E.183 (03/98) 6.3 Presentation of n
35、umerical information Numerical information, and in particular telephone numbers, can be more easily remembered if spoken in a familiar manner. This may necessitate different rules for different countries, and may be influenced by such things as numbering plan and custom. (For example, a 3- or 4-digi
36、t area code separated by a pause from a 5- or 6-digit local number. The number 7230 could be spoken as “seven, two, three, oh“ or “seventy-two, thirty“ or “seven, two, three, zero“). In many languages, three intonation patterns are required for telephone numbers: a neutral pattern for the body of th
37、e number, a continuant pattern for the end of an intermediate block (rising pitch), and a terminator for the end of the number (falling pitch). Number strings are more easily remembered if spoken with a rhythm based on the perceptual centres of utterances (e.g. digits), rather than with one based on
38、 the start of the utterance period. The final determinant of what is required in a particular case depends upon the iterative procedure of listening, editing and judging previously mentioned. 6.4 Update problems Problems may arise when an announcement has to be changed such that a word or words have
39、 to be either rerecorded or recorded for the first time. There may be difficulty in obtaining the original speaker, and even if the original speaker is available, the voice may differ f-om the original recording, either temporarily (e.g. by a head cold) or permanently (e.g. through ageing). This can
40、 mean that the entire vocabulary has to be recorded again, or alternatively, an announcement of degraded quality may be accepted as an expedient solution. Wherever possible, problems of this sort should be anticipated, and recordings made of a larger vocabulary than is to be used immediately. 7 Tone
41、s and announcements for use in telephone services The problems associated with “concatenated-word“ systems outlined above are avoided by the use of truly synthetic speech generated by rule. These rules translate a specification of what utterance is to be generated into acoustic output. If appropriat
42、e rules are found, this method can potentially generate high quality speech, and such features as speed of delivery, duration of pauses, and stress and pitch changes can be readily specified. One approach to the development of such systems starts with the use of natural speech analysis as the source
43、 for generating rule parameters, and leads on to the derivation of general des to convert any message into speech output. Rule-generated synthetic speech is currently on the threshold of full functional equivalence with that produced by waveform storage methods, such as word concatenation. However,
44、even highly intelligible synthetic speech sounds unnatural and it may not be as acceptable to users as “concatenated-words“ announcements, at least in the immediate future. 8 The preferred listening level is -10 dBPa k 5 dB measured at the customers ear. The recommended sending level to achieve this
45、 listening level can be found in Recommendation G.115. Preferred listening levels for announcements Recommendation E.183 (03198) 3 STD.1Ti.J-T RECMN Ee383-ENGL 3998 m 4862593 0648689 153 m Series A Series B Series C Series D Series E Series F Series G Series H Series I Series J Series K Series L Ser
46、ies M Series N Series O Series P Series Q Series R Series S Series T Series U Series V Series X Series Y Series Z ITU-T RECOMMENDATIONS SERIES Organization of the work of the ITU-T Means of expression: definitions, symbols, classification General telecommunication statistics General tariff principle
47、s Overall network operation, telephone service, service operation and human factors Non-telephone telecommunication services Transmission systems and media, digital systems and networks Audiovisual and multimedia systems Integrated services digital network Transmission of television, sound programme
48、 and other multimedia signals Protection against interference Construction, installation and protection of cables and other elements of outside plant TMN and network maintenance: international transmission systems, telephone circuits, telegraphy, facsimile and leased circuits Maintenance: internatio
49、nal sound programme and television transmission circuits Specifications of measuring equipment Telephone transmission quality, telephone installations, local line networks Switching and signalling Telegraph transmission Telegraph services terminal equipment Terminals for telematic services Telegraph switching Data communication over the telephone network Data networks and open system communications Global information infrastructure Programming languages Printed in Switzerland Geneva, 1998
