1、QUESTION ITU-R 212-2/3Ionospheric properties(1978-1982-1990-1997-2009)The ITU Radiocommunication Assembly,consideringa) that ionized media affect the propagation of radiowaves;b) that a large number of digitized measurements are now available which cover all levels ofsolar activity for 3-4 eleven-ye
2、ar solar cycles,decides that the following Questions should be studied1 What additional information concerning the properties of the terrestrial ionosphere andionized regions beyond would facilitate the study of aspects of propagation that are important toradio systems?2 What physical properties and
3、 what variations in the structure of the ionosphere, in particularat or near the magnetic equator and at high latitudes, have an influence on radiocommunications?3 What improvements may be made to the mapping of ionospheric characteristics on botha global and regional basis using data and analysis techniques now available?further decides1 that appropriate information shall be included in a Recommendation;2 that the above studies should be completed by 2013.Category: S3
