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Direct-broadcast satellite


A direct-broadcast satellite (DBS) is a type of artificial satellite which usually broadcasts satellite television signals for home reception.

The type of satellite television which uses direct-broadcast satellites is known as direct-broadcast satellite television (DBSTV) or direct-to-home television (DTHTV). The term "direct broadcast" is used to distinguish satellites which transmit radio or television signals directly to receivers in consumers' homes from other communications satellites which transmit signals to satellite ground stations, for example those which distribute cable television signals to cable head end facilities. Since home satellite television receivers use small dish antennas less than a meter in diameter, DBS satellites must have much higher downlink transmitter power than other communication satellites, which are received by larger dishes from 2 up to 50 meters diameter.

In Europe, prior to the launch of Astra 1A in 1988, the term DBS was commonly used to describe the nationally commissioned satellites planned and launched to provide television broadcasts to the home within several European countries (such as BSB in the United Kingdom and TV-Sat in Germany). These services were to use the D-Mac and D2-Mac format and BSS frequencies with circular polarization from orbital positions allocated to each country. Before these DBS satellites, home satellite television in Europe was limited to a few channels, really intended for cable distribution, and requiring dishes typically of 1.7 m.

SES launched the Astra 1A satellite to provide services to homes across Europe receivable on dishes of just 90 cm and, although these mostly used PAL video format and FSS frequencies with linear polarization, the DBS name slowly came to be applied to all Astra satellites and services too.


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