| 摘要 |
The CCIR,
CONSIDERING
(a) that selective calling of ships by coast stations would expedite the handling of traffic in the maritime mobile service;
(b) that a selective-calling system has the following advantages:
?C it is rapid and positive;
?C it overcomes the disadvantages of ships having to listen to all calls;
?C it reduces the difficulties caused by differences of language;
?C it reduces the time taken by coast stations to establish contact with ships and thus reduces congestion on the channels used for calling;
?C it increases operating efficiency generally;
(c) that a number of administrations have an immediate requirement for selective-calling facilities;
(d) that ideally, a selective-calling system should be suitable for use in all maritime mobile bands;
(e) that a selective-calling system should have sufficient capacity of code numbers to accommodate all ships that desire to use it;
(f) that the International Maritime Organization (IMO) has expressed in its letter of 2 November, 1966, the opinion that it would be desirable from the viewpoint of maritime safety, if selective-calling devices could include a facility for calling all ships;
(g) that there may be a need for a facility to call predetermined groups of ships;
(h) that it may be operationally desirable for a ship’s operator to be able to ascertain either the identity of the coast station which has called him, or the VHF channel on which he should reply;
(j) that a selective-calling system should be suitable for use with normal types of radio equipment on ships |
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