1、110 Rec. ITU-R V.666-2 RECOMMENDATION ITU-R V.666-2 ABBREVIATIONS AND INITIALS USED IN TELECOMMUNICATIONS (1986-1998- 1993) The ITU Radiocommunication Assembly, considering the rapid increase in the number of abbreviations and initials used in the texts of the ITU; that it is sometimes difficult to
2、find the precise meaning of an abbreviation or acronym appearing in a text of a) b) the ITU, recommends that, as far as the use of abbreviations in texts of the ITU is concerned, the following guidelines be taken into account. I. Abbreviations should not be used in titles. 2. The use of abbreviation
3、s should be as far as possible limited to those in current use. 3. Within each technical area (corresponding to a Study Group or a Working Party) the meaning of the abbreviations currently in use, as well as the corresponding abbreviations in the other working languages, should be given in a Recomme
4、ndation (or an Annex to a Recommendation on terminology). 4. The use of abbreviations specific to a text (or to a set of neighbouring texts) should be limited to cases when they make the text easier to read, i.e. when an abbreviation may be used a number of times in the same text, or is used in a ta
5、ble or a diagram. 5. In each text, the meaning of any abbreviation shall be given when this abbreviation is used for the first time; furthermore, the meaning of abbreviations used in a text should be recalled in an alphabetical list at the end of the text, or in the legend of tables or diagrams. 6.
6、case of specific abbreviations quoted in 5 4 above. 7. be avoided. As far as possible, the same abbreviation should be used in the different working languages, in particular in the The use of abbreviations comprising less than three characters, which is the source of many confusions, should 8. Appen
7、dix 1 gives a number of references to texts giving the meaning of abbreviations used in some particular areas. Note I - An alphabetical list of abbreviations used in the Blue Book fascicles of the former CCITT is published in Volume 1.3 of this publication. APPENDIX 1 References to lists of specific
8、 abbreviations 1. Frequency and wavelength bands See Recommendation ITU-R V.43 1. 2. Alphabets, codes, routing codes and identities See the relevant ITU-T Recommendations (Index of the Blue Book, Fascicle 1.4). ITU-R RECMN*V- bbb-2 93 M 4855212 0523498 Tb8 W Rec. ITU-R V.666-2 3. Codes contained in
9、the Radio Regulations Designation of emissions: Article 2. Symbols for the various types of antenna: Appendix 2, section III. Q code, general section (QRA to QUZ): Appendix 13, section I. Miscellaneous abbreviations: Appendix 13, sections I and TI. SINPO and SINPFEMO codes: Appendix 15. 3. I 3.2 3.3
10、 3.4 3.5 i11 4. Abbreviations used by the ITU for the names of countries See the preface to the International Frequency List, Table I. (Different abbreviations have been approved by the International Organization for Standardization (ISO), see IS0 Standard 3 166.) 5. Acronyms of international organi
11、zations involved in telecommunications See the ITU “Global Directory” section 2. 6. Symbols and names for units 6.1 27 and to IS0 International Standards 31 and 1000. Recommendation ITU-R V.430 gives the sources to be used. This Recommendation refers to IEC Publication 6.2 Recommendation ITU-R V.607
12、: Terms and symbols for information quantities in telecommunications. 6.3 Recommendation ITU-R V.574: Use of the decibel and the neper in telecommunications. 6.4 Recommendation ITU-R V.665: Traffic intensity unit. 7. Letter symbols Recommendation ITU-R V.608: “Letter symbols for telecommunications”
13、provides guidelines io be followed to simplify the reading of documents dealing with telecommunication techniques: it refers to IEC Publication 27 and to IS0 International Standard 3 1 for letter symbols to represent physical quantities and mathematical operations. 8. Chemical symbols See the table published by the International Union of Pure and Applied Chemistry (IUPAC).