The Ku-band (Kurtz-under band) is particularly used for broadcasting satellite television. This band is split into multiple segments broken down into geographical regions, as the ITU (International Telecommunication Union) determines.
The most common Ku-band digital reception format is DVB (main profile video format) versus the studio profile digital video format or the full-blown Digicipher II 4DTV format. The first commercial television network to extensively utilize the Ku-band for most of its affiliate feeds was NBC, back in 1983.
The 12.2 to 12.7 GHz segment of the Ku-band spectrum is allocated to the broadcasting satellite service (BSS). These direct broadcast satellites typically carry 16 to 32 transponders. Each provides 27 MHz in bandwidth and consumes 100 to 240 W each, accommodating receiver antennae down to 450 mm (18 in).
When frequencies higher than 10 GHz are transmitted and received in a heavy rainfall area, a noticeable degradation occurs, due to the problems caused by and proportional to the amount of rainfall. This problem can be combated, however, by deploying an appropriate link-budget strategy when designing the satellite network and allocating a higher power consumption to overcome rain fade loss. In terms of end-viewer TV reception, it takes heavy rainfalls in excess of 100 mm per hour to have a noticeable effect.
Ku-band's higher frequency spectrum is particularly susceptible to signal degradation, considerably more than C-band satellite frequency spectrum, though the Ku-band is less vulnerable to rain fade than the Ka-band frequency spectrum.
Ku-band satellites typically require considerably more power to transmit than C-band satellites. However, both Ku- and Ka-band satellite dishes are smaller.
The Ku-band downlink uses frequencies between 11.7 and 12.7 GHz. Services that can be found on the Ku-band include educational networks, business networks, sports backhauls, teleconferences, mobile news truck feeds, international programming, various SCPC (single channel per carrier) transmissions of analog audio, as well as FM audio services.
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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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