U.S. DTV on Cable
Since FCC’s adoption of DTV standards in the U.S. in 1996, the number of DTV stations on the air has increased to 200+ stations by end of 2001, and has almost doubled that in the first half of 2002 alone. The numbers represent over 90% of U.S. households have access to at least one digital broadcast over the air. The cable companies, who control access to 70% of U.S. homes, are refusing to carry the DTV signals from broadcasters, citing a variety of technical problems. This study looks into the status of cable industry’s analog-to-digital transition, in order to help MDEA’s commitment to DTV
Background & Objective: MDEA is the leading manufacturer of DTV sets in North America. Cable DTV standard is different compared to the broadcast DTV standard. The goal is to investigate how MDEA can take advantage of the digital potential from cable.
Technical Discussion: Cable allows system information to be delivered out-of-band, which is a dramatic departure from the terrestrial broadcast. An out-of-band transmission means DTV receivers must also monitor the signal from another frequency, and thus increases the complexity of the receiver design. Document SCTE/DVS 234 is an approved document to standardize the scheme for out-of-band system information deliveries. SCTE/DVS 241 on the other hand describes the transport layer characteristics and normative specifications of the in-band service multiplex and transport system standard for cable DTV. One of the more important standard on the cable is SCTE/DVS 295, which defines the characteristics and normative specifications for the interface between Point of Deployment (POD) security modules owned and distributed by cable operators, and commercially available consumer receivers and set-top terminals (host devices) that are used to access multi-channel television programming carried on North American cable systems. In addition SCTE/DVS 301 further defines the POD standard to include copy protection for content delivery to the receiver, with a goal of preventing unrestricted copying of high valued contents. Most recently SCTE/DVS 311 was developed to describe the methods to transmit multicast IP data over MPEG 2 digital transport streams.
Contacts:
Kent Wittenburg
Technology Area: Advanced Digital Television
Modification Date: January 23, 2007
