Digital Satellite System
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Digital Satellite System (DSS), or Direct Broadcast Satellite (DBS), is a technology to deliver a television or audio signal digitally, directly from an orbiting satellite to a consumer's one- to three-foot-diameter dish at the consumer's home or business. DBS is seen as an alternative (and competitor) to cable TV.
DBS systems can always provide more channels of content than an analog cable TV system; however, with the advent of digital cable, this distinction is no longer true. In some cases, DBS can be less expensive than Cable TV, and competition between the two means of content delivery has increased since the introduction of DBS. Cable TV in the United States is regulated by the Federal Communications Commission (FCC), whereas DBS companies are largely unregulated; this distinction can also lead to price differences. Analog cable TV is more susceptible to reception interference than any digital means of delivery, so this is an advantage which DBS companies tout. In the United States, a DBS dish requires a clear view of the southern sky, and stormy weather can block a DBS signal and prevent viewing.
The digital signal from the DBS satellites is encoded into a compressed format and encrypted to prevent unauthorized/unpaid viewing. The customer must purchase or rent a decoder/decrypter console unit which converts these signals into a regular video signal. It is still rare, but increasingly, HDTV-capable DBS decoder boxes and services are becoming popular; many consoles also include DVR functionality. When first introduced, consumers paid several hundred dollars to purchase the consoles, but prices steadily have fallen. Now most DBS service providers will supply a free decoder box for a service commitment from the customer.
The decoder boxes typically use a subscription card to store information on which channels the customer is authorized to view. A black market has emerged in selling/trading custom or "hacked" cards, which enable the customer to view many more channels than he/she has purchased. The DBS companies are constantly looking for ways to circumvent these pirate cards, and criminal or civil prosecution of offenders is possible though unlikely.
Customers are often confused about the word "digital" when used with "Digital Satellite System" or "digital cable". These technologies are digital only in that the content is delivered to the consumer by digital means. The means of delivery is independent of whether the content delivered is in an actual DTV format (such as HDTV). DBS and digital cable originally broadcasted standard analog (NTSC) television, and DTV capability is being slowly added to each system. DTV can also be broadcast by conventional means, and indeed all local HDTV television stations broadcast an over-the-air HDTV signal.
The two largest DBS television providers in the United States are DirecTV and the EchoStar Dish Network. Britain's predominant Digital television provider is SKY, which contains fully interactive, on-demand material. The box is connected to a household phone line and received via minidish.
External Links
- Digital Insurrection (http://satellitetv.digitalinsurrection.com)