| 摘要 |
The CCIR,
CONSIDERING
(a) that, for a user, data concerning the error of a standard-frequency and time-signal emission are of great importance;
(b) that the International Atomic Time scale (TAI) has considerable importance as a reference for time and frequency comparisons;
(c) that, in many cases, it is technically possible to adjust a radiated standard frequency so that the variations of phase with respect to TAI or Coordinated Universal Time (UTC) remain within a narrow tolerance ± Dt, which is small compared to the period of the carrier frequency;
(d) that the TAI frequency and the UTC frequency are identical;
(e) that equipment is available which is capable of receiving several nearly synchronous emissions, thereby providing alternative operation in case of transmitter interruption;
(f) that there is a need for universally accepted reference frequencies for use in electronic systems;
(g) that there is an ever-increasing need for frequencies of high stability, particularly with regard to data transmission;
(h) that many new precisely controlled electronic systems (e.g. those controlled by atomic frequency generators) are now coming into use;
(j) that these systems can be better coordinated if they use a common frequency reference |
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