BroadBand Technologies Inc will integrate encoding and compression technology from AT&T Microelectronics into its Fibre Loop Access System that will enable twisted pair cabling to carry speech, data and broadband digital interactive services. The move is aimed at making fibre-to-the-kerb installations – where fibre optic cable is laid in the street, with pick-off points for copper cabling into the home – far cheaper for consumers. Fibre Loop Access System is a network access switched digital video system that runs over the fibre-to-kerb network. It incorporates Asynchronous Transfer Mode switching and transport and Moving Pictures Expert Group video compression standards. It has been developed to provide combined telephone and cable television services, including interactive channels such as educational programmes, home shopping and so on, over the same cabling to people’shomes. Research Triangle Park, North Carolina-based Broadband says that the system provides unlimited bandwidth and greater immunity to electromagnetic interference. The switched digital video architecture provides dedicated downstream bandwidth and dedicated upstream signalling. Fibre Loop Access System’s enhancement with the encoding technology means that service providers, such as telephone or cable television companies, could install common equipment for a telephone service and interactive video. AT&T’s contribution is 16-Carrierless Amplitude and Phase Modulation, 16-CAP, an encoding and compression technology developed by AT&T Bell Laboratories that enables analogue transmission of up to 51.84M-bits per second over 300 feet or more of unshielded copper pair wiring, from the kerb box into the house.
Triples capacity
AT&T says 16-CAP effectively triples the previous data transmission capacity of the cabling. AT&T says it reduces the bandwidth required for video transmission to one quarter of what is required for non-encoded video and can be accomplished without the use of carrier modulation schemes or forward error correction, so using less electronics and making it cheaper than other encoding and modulation technologies to implement. The technology is derived from high-speed modems and is the technology that the ATM Forum is in the process of voting on as the 51.84Mbps standard; if ac-cepted it will probably be used to introduce Asynchronous Transfer Mode into the Information Superhighway in the US. It can sit in the set-top box on a television or at the kerb-side as an interface between the digital interactive video network and the twisted pair cable. With it, Broadband’s Fibre Loop Access System will provide standard broadcast cable services, for customers that just want that service, over the same cabling as the interactive services. This will enable the re-use of existing telephone analogue twisted pair to the home and coaxial cable within the home. The price of this system has not been revealed but it is expected to be available by the end of the year. AT&T is marketing 16-CAP to television set-top box manufacturers and network providers. Broadband Technologies’ Fibre Loop Access System is being used by Bell Atlantic Corp in its commercial video dialtone network trial under way in Toms River, New Jersey and the Bell just bought a stake in the company.
