ITU-R M 540-2-1990 OPERATIONAL AND TECHNICAL CHARACTERISTICS FOR AN AUTOMATED DIRECT-PRINTING TELEGRAPH SYSTEM FOR PROMULGATION OF NAVIGATIONAL AND METEOROLOGICAL WARNINGS AND URGE.pdf

1、CCIR VOLUME*VIII 90 m 4855232 0533393 2 m - Rec. 540-2 119 RECOMMENDATION 540-2 * OPERATIONAL AND TECHNICAL CHARACTERISTICS FOR AN FOR PROMULGATION OF NAVIGATIONAL AND METEOROLOGICAL WARNINGS AND URGENT- INFORMATION TO SHIPS AUTOMATED DIRECT-PRINTING TELEGRAPH SYSTEM (Question 5/8) (1978-1982-1990)

2、The CCIR, CONSIDERING (a) of great importance for safety; (b) ings and urgent information to ships can be improved by use of modern techniques; that the availability of navigational and meteorological warnings and urgent information on board ships is that the existing- radiocommunication system for

3、promulgation of navigational and meteorological warn- (c) - that the IMO has etablished the following definitions on the promulgation of maritime safety information: “NAVTEX” means the system for the broadcast and automatic reception of maritime safety information by means of narrow-band direct-prin

4、ting telegraphy; “international NAVTEX service” means the coordinated broadcast and automatic reception on 518 kHz of maritime safety information by means of narrow-band direct-printing telegraphy using the English language, as set out in the NAVTEX manual, published by the IMO; “national NAVTEX ser

5、vice” means the broadcast and automatic reception of maritime safety information by means of narrow-band direct-printing telegraphy using frequencies and languages as decided by the adminis- trations concerned; (d) that the 1988 Amendments to the International Convention for the Safety of Life at Se

6、a, 1974, require that every ship to which the Convention applies shall be provided with a receiver capable of receiving international NAVTEX service broadcasts; - - (e) direct-printing in accordance with Article 14A of the Radio Regulations; (f) (g) (h) characteristics would facilitate the extension

7、 of the service, that several countries are operating a coordinated international NAVTEX service, based on narrowband that the system should be applicable to the maritime mobile service (both international an3 national); that it is desirable that the service fulfils the requirements of all types of

8、ships desiring to use it; . that although each area may need specific guidance, the use of standard technical and operational UNANIMOUSGY RECOMMENDS 1. urgent information using NBDP should be in accordance with Annex I; that the operational characteristics for the promulgation of navigational and me

9、teorological warnings and 2. urgent information using NBDP should be in accordance with Annex II. that the technical characteristics for the promulgation of navigational and meteorological warnings and The Director, CCIR, is requested to bring this Recommendation to the attention of the Internationa

10、l Maritime Organization (IMO), the International Hydrographical Organization (IHO), the World Meteorological Organization (WMO) and to the International Association of Lighthouse Authorities (IALA). fi m F - 7 - COPYRIGHT International Telecommunications Union/ITU RadiocommunicationsLicensed by Info

11、rmation Handling Services120 CCIR VOLUME*VIII 90 W 4855232 0533392 4 Rec. 540-2 ANNEX I OPERATIONAL CHARACTERISTICS 1. Narrowband direct-printing techniques should be used for an automated telegraph system for promulga- tion of navigational and meteorological warnings and urgent information to ships

12、. Common frequencies for such transmissions should be internationally agreed upon and the frequency 518 kHz has been designated for world-wide use in the international NAVTEX service (see Radio Regulations Nos. 474, 2971B and N2971B). 1.1 For national NAVTEX services administrations should also util

13、ize the format of this Recommendation on the appropriate frequencies as defined in the Radio Regulations. 2. service area of that coast station. The range extension o.ccurring during night hours should also be considered. The radiated power from the coast station transmitter should only be that suff

14、icient to cover the intended 3. single frequency (Resolution No. 324 (Mob-87). 4. anticipated messages to be broadcast to the area concerned. 5. interference with broadcasts from other stations. The information transmitted should primarily be of the type used for coastal waters preferably using a Th

15、e transmission time allocated to each station should be restricted to that which is adequate for the Scheduled broadcasts should take place at intervals not exceeding eight hours and be coordinated, to avoid 6. Message priorities 6.1 NAVTEX service. In descending order of urgency they are: - VITAL:

16、- - ROUTINE: for broadcast at the next scheduled transmission period. Note - Both VITAL and IMPORTANT warnings will normally need to be repeated, if still valid, at the next scheduled transmission period. Three message priorities are used to dictate the timing of the first broadcast of a new warning

17、 in the for immediate broadcast, subject to avoiding interference to ongoing transmissions; IMPORTANT: for broadcast at the next available period when the frequency is unused; 6.2 In order to avoid unnecessary disruption to the service, the priority marking VITAL is to be used only in cases of extre

18、me urgency, such as some distress alerts. In addition, VITAL messages are to be kept as brief as possible. 6.3 Periods should be scheduled between the regular transmission periods permitting immediate/early trans- mission of VITAL messages. 6.4 By use of the message serial number O0 in the preamble

19、of a message (see also Annex II 0 6) it is possible to override any exclusion of coast stations or of message types which might have been made in the receiving equipment. 7. Initial shore-to-ship distress-related messages should first be broadcast on the appropriate distress frequency by coast stati

20、ons in whose SAR area distress cases are handled. 8, . - - Participating transmitting stations should be provided with monitoring facilities to enable them to: monitor their own transmissions as to signal quality and transmission format; confirm that the channel is not occupied. 9. (e.g. for better

21、coverage) the original preamble B,-B4 (see Annex II) should be used. In case a message is repeated by more than one transmitting station within the same NAVTEX region 10. language is used it shall be English. In order to avoid overloading of the channel it is desirable to use a single language and w

22、here a single 11. Dedicated on-board equipment is recommended. 12. the International Maritime Organization. - Other operational characteristics and detailed guidance are given in the NAVTEX Manual developed by COPYRIGHT International Telecommunications Union/ITU RadiocommunicationsLicensed by Inform

23、ation Handling ServicesCCIR VOLUME*VIII 90 = 4855232 0533393 b = - Carriage Phasing signals One return a10 s zczc space B1B2B3B4 - line feed Rec. 540-2 121 Carriage return 2 line feeds Message NNNN + 3 ANNEX II TECHNICAL CHARACTERISTICS 2. specified in Recommendations 476 and 625. The signals transmitted should be in conformity with the collective B-mode of the direct-printing system COPYRIGHT International Telecommunications Union/ITU RadiocommunicationsLicensed by Information Handling Services