The Early Days
In the 1970's and 1980's, satellites became a chief means of long distance radio communication and facilitated worldwide TV program distribution in real time. In rural areas not serviced by terrestrial TV broadcast stations and cable TV systems, satellite signals made possible direct reception of TV from satellites by TVRO receivers equipped with parabolic antennas with diameters between 2 and 5 meters. For almost two decades, TV program delivery by satellites was done in the 4/6 GHz C-band and 11-14 GHz Ku-FSS bands. (FSS-Fixed Satellite Service)
The Emergence of the "Small Dish"
In the early 90's, advancements in radio communications technologies and the offer of a smaller, more marketable "Small Dish TV" paved the way for DirecTV and later, Dish Network. These new Direct Program Providers use a sub-band of Ku-FSS (11-14 GHz), the Broadcast Satellite Service Band (BSS-12.2 to 12.7 GHz). Today, three technologies have been aggressively developed for the BSS: the direct broadcast service (DBS), BSS-HDTV, and BSS-Sound. The frequencies for the DBS uplink (Earth-to-space direction), are allocated in the FSS. Downlink DBS frequencies are allocated in the BSS.
Ku-BSS satellites broadcast at higher powers then the first Ku-FSS satellite. FSS satellites use broadcast powers around 50-60 watts, and are positioned in orbit as close as 2 degrees, relative. BSS satellites, which include the DBS satellites used by DirecTV and Dish Network use broadcast powers as high as 200 watts. This increased power requires the satellites to be spaced at least 9 degrees apart to maintain signal separation when using a smaller dish. Satellite Dishes for FSS Ku-band reception are usually no smaller then 26-36 inches in diameter. DBS Ku-band satellite dishes can operate as small as 14 inches, but 18 inches is considered the smallest dish size for reliable residential use.
The Next Generation
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