Date Added: Jul 2011
Sources responsible for generating noise in the magnetospheric and ionospheric cavities with reference to the relative power levels in different frequency bands are examined. Some propagation characteristics of both atmospheric and cosmic radio noise as recorded at Kalyani have been examined. The characteristics obtained are compared with other reported results. The terrestrial environment is exposed to electromagnetic radiation continuously producing background electromagnetic noise. For frequency below 300 GHz i.e. within the Non Ionizing Radiation (NIR) band this background noise can have a natural origin which is generally atmospheric or cosmic.