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Single Cable Distribution is a satellite TV technology that enables the delivery of broadcast programming to multiple users over a single coaxial cable, and eliminates the numerous cables required to support consumer electronics devices such as twin-tuner Digital Video Recorders (DVRs) and high end receivers. Without single cable distribution, providing full spectrum access for multiple receivers, or receivers with multiple tuners, in a single family home has required a separate coaxial cable feeding each tuner from the antenna equipment (either multiple LNBs, a multi-output LNB or a multiswitch distribution system) because of the large bandwidth requirement of the signals. Single cable distribution technology enables one coaxial cable from the antenna equipment to multiple tuners, to provide independent tuning across the whole range of satellite reception for each tuner.〔SES ASTRA "Single Cable Distribution" (August, 2008). Company factsheet〕 A European industry standard for distributing satellite signals over a single coaxial cable - CENELEC EN50494 - has been defined in 2007〔(ansi.org - BS EN 50494:2007 Satellite signal distribution over a single coaxial cable in single dwelling installations (British Standard) ) $257 read 2012-06-29〕 and developed by a consortium led by SES. Single cable distribution technology can be found in commercial equipment with the Unicable trademark from FTA Communications Technologies. Unicable uses an integrated software and hardware solution that allows Unicable-certified Digital Video Recorders and receivers to multiplex selected programming when using Unicable LNB or multiswitching products. The Unicable Interoperability Platform is open to companies designing and/or marketing satellite and other broadcast-related products. The platform is designed to facilitate the acceptance of Unicable-certified solutions in the consumer TV broadcast market. == How it works == Each satellite receiver in the installation has a dedicated user band of a bandwidth approximately the same as a transponder. The receiver requests a particular transponder frequency via a DiSEqC-compliant command. A mixer in the dish-end equipment (an LNB or distribution unit) converts the received signal to the correct user band IF centre frequency for that receiver.〔Bains, Geoff. "Inverto Unicable LNB" ''What Satellite & Digital TV'' (February, 2006) pp60-62〕 The converted transponders of the various users are then combined, and sent via the single coaxial cable to the receivers. The combined signal is tapped or split to reach every user. Silicon vendors have developed complex Integrated Circuits that greatly reduce the cost of implementing the single cable distribution function. A Channel Stacking Switch IC is a multiple-input multiple-output device. It typically has N inputs that can be cascaded to additional chips as required (to expand output capacity). These inputs are fed into a large N-pole M-Throw switch that outputs to . Each mixer path then translates only the user requested transponder to a predetermined fixed frequency within the band. This fixed frequency is unique for each tuner on the single cable output. Each tuner in the STB always stays at this fixed frequency while the CSS IC translates the user requested content down the cable to this exact frequency. This architecture requires no hardware change to the STB design. Communications protocol between the CSS IC and the STB is handled via the CENELEC EN50494 standard or proprietary systems.〔(ENTROPIC ) - Single Cable Distribution White Paper, Brandon, Troy. "Changing DBS Delivery - The Single Wire Solution" (2008)〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Single cable distribution」の詳細全文を読む スポンサード リンク
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