1、- 1 -3/1(Add.1)-EQUESTION ITU-R 228-1/3*Propagation data required for the planning of radiocommunicationsystems operating above 275 GHz*(2000-2005)The ITU Radiocommunication Assembly,consideringa) that the spectrum in many of the frequency bands used for radiocommunication isincreasingly congested a
2、nd this problem is expected to get worse;b) that telecommunication links are being used or planned for use on some terrestrialapplications at frequencies above 275 GHz;c) that telecommunication links are being used or planned for use on some satellite systemsfor inter-satellite communications at fre
3、quencies above 275 GHz;d) that the viability of telecommunication links operating above 275 GHz (space-to-Earth andEarth-to-space) is currently being investigated;e) that remote sensing and astronomical applications are using frequencies above 275 GHz;f) that interest exists in extending the range o
4、f frequencies used for telecommunicationapplications;g) that the focus of study of Questions by Radiocommunication Study Groups includes thefollowing: use of the radio-frequency spectrum in radiocommunication; characteristics and performance of radio systems; operation of radio systems;_* This Quest
5、ion should be brought to the attention of Radiocommunication Study Groups 1, 7 and 9.* The frequency spectrum above 275 GHz is currently not allocated (see also No. 5.565 of the RadioRegulations).- 2 -3/1(Add.1)-Eh) that propagation models are urgently required for planning and design oftelecommunic
6、ation systems at frequencies above 275 GHz,notingthat according to No. 78 of the ITU Constitution and Note 2 of No. 1005 of the ITU Convention,study groups may adopt Recommendations without limit of frequency range,decides that the following Question should be studied1 What models best describe the
7、relationship between atmospheric parameters andelectromagnetic wave characteristics on terrestrial, space-to-Earth and Earth-to-space linksoperating at frequencies above 275 GHz?2 What models best describe the relationship between free-space parameters andelectromagnetic wave characteristics on inte
8、r-satellite links operating at frequencies above275 GHz?3 What models best describe the relationship between atmospheric parameters andelectromagnetic wave characteristics on science service links operating at frequencies above275 GHz?4 What models best describe the relationship between atmospheric
9、parameters and theminimum practical altitude for space-to-space links operating at frequencies above 275 GHz?further decides1 that the results of studies above 275 GHz should be brought to the attention of the otherStudy Groups;2 that the results of the above studies should be included in one or more Recommendations;3 that the results related to terrestrial applications should be available by 2006, and should beincluded in future Recommendation(s) or Report(s).Category: C1
