1、QUESTION ITU-R 110-2/7*Time codes (1990-1993-1997) The ITU Radiocommunication Assembly, considering a) the need to provide a complete and unambiguous time reference for a variety of scientific and industrial applications; b) that a number of standard-frequency and time-signal stations now transmit t
2、ime codes giving at least minute, hour, and day-of-year information; c) that it is very desirable that such codes be compatible with each other and with commonly available commercial equipment; d) that details are not readily available on the various time codes which have been developed for system a
3、pplications, and that unnecessary proliferation is undesirable, decides that the following Question should be studied 1 What types and formats can be recommended for the transmission of time code information? 2 What modulation characteristics will best ensure reliable decoding under conditions of no
4、ise and interfering signals? 3 What are the currently used time codes, and is the detailed information on them from available sources adequate to enable the selection of the codes best suited to particular systems applications? further decides 1 that the results of the above studies should be included in (a) Recommendation(s); 2 that the above studies should be completed by 2011. NOTE 1 See Recommendation ITU-R TF.583. _ *In the year 2009, Radiocommunication Study Group 7 extended the completion date of studies for this Question.