C-band satellites use 3.7-4.2 GHz band of frequencies for downlinking and 5.925-6.425 GHz for uplinking.
C-band satellites have 24 radio transponders spaced 20 MHz apart, but with the adjacent transponders on opposite polarizations. Hence, the transponders on the same polarization are always 40 MHz apart. Of this 40 MHz, each transponder utilizes about 36 MHz.
C-band is primarily used for open satellite communications, whether for full-time satellite TV networks or raw satellite feeds, although subscription programming also exists. This use contrasts with direct broadcast satellite, which is a completely closed system used to deliver subscription programming to small satellite dishes that are connected with proprietary receiving equipment.
The satellite communication portion of the C-band is highly associated with television receive-only satellite reception systems, commonly called big dish systems, since small receiving antennae are not optimal for C-band systems. Typical antenna sizes on C-band capable systems ranges from 7.5 to 12ft (2.5 to 3.5 m) on consumer satellite dishes, although larger ones can also be used.
The C-band frequencies of 5.4 GHz band (5.15 to 5.35 GHz, or 5.47 to 5.725 GHz, or 5.725 to 5.875 GHz, depending on the region of the world) are used for IEEE 802, leading to occasional interference with some weather radars that are also allocated to the C-band.
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(Useful for UPSC General Studies, APPSC Group 1 Group 2 , Mains Material, Paper 1, Paper 4 Section 1 Section 2 Section 3, ROLE AND IMPACT OF SCIENCE AND TECHNOLOGY IN THE DEVELOPMENT OF INDIA, GENERAL AWARENESS WITH THE MODERN TRENDS IN LIFE SCIENCES, DEVELOPMENT & ENVIRONMENT PROBLEMS)
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