SpectrumTalk

Mobile DTV Standard Adopted by Industry

On Friday the Open Mobile Video Coalition (OMVC), "an alliance of U.S. commercial and public broadcasters formed to accelerate the development and rollout of mobile DTV products and services" issued this press release:

OMVC ... today announced it is “All Systems Go” for a new era of television service on mobile devices. With Thursday’s adoption of a final mobile digital television (Mobile DTV) broadcast standard by the Advanced Television Systems Committee (ATSC), U.S. broadcasters are poised to roll out an array of digital program services that will be available to consumers on devices ranging from in-car screens to portable DVD players and mobile phones.

“I congratulate ATSC for its remarkable achievement in bringing this standard to fulfillment. Mobile DTV utilizes the same digital spectrum that local TV stations use to send beautiful HD programming to the nation’s living rooms. With adoption of the ATSC Mobile DTV standard, small-screen versions of that programming and other services also will now be available over mobile devices,” said Brandon Burgess, president of the OMVC and CEO of ION Media Networks.

OMVC today demonstrated the services enabled by the new standard during a Mobile DTV briefing for government officials and others on a bus traveling around the Nation’s Capital. Seven Washington-area TV stations transmitted live local news, weather, sports and favorite programs to Mobile DTV compatible devices including mobile phones, laptop computers and netbook PCs. Senior representatives of the participating DTV stations, ATSC, the Association for Maximum Service Television (MSTV), the National Association of Broadcasters (NAB) and technology companies participated in the dialog about the new standard and the new mobile services it will support.

Broadcasting & Cable, the prime cheerleader for broadcasters, has this quote:

Paul Karpowicz, NAB Television Board chairman and president of Meredith Broadcast Group, added, "This milestone ushers in the new era of digital television broadcasting, giving local TV stations and networks new opportunities to reach viewers on the go. This will introduce the power of local broadcasting to a new generation of viewers and provide all-important emergency alert, local news and other programming to consumers across the nation."

In case you want to know what this system actually is, an ATSC document with real details is here. A brief summary from p. 12-13 of this document states:

The M/H system provides mobile/pedestrian/handheld broadcasting services using a portion of the ~19.39 Mbps ATSC 8-VSB payload, while the remainder is still available for HD and/or multiple SD television services. The M/H system is a dual-stream system—the ATSC service multiplex for existing digital television services and the M/H service multiplex for one or more mobile, pedestrian and handheld services.

Central to the M/H system are additions to the physical layer of the ATSC transmission system that are easily decodable under high Doppler rate conditions. The requirements for these additions are defined in this Part. Extra training sequences and forward error correction (FEC) are added to assist reception of the enhanced stream(s).

So the new system, formally A/153, just takes capacity from the 19.4 Mb/s that "free"/over-the-air DTV is sending in a 6 MHz TV channel and diverts it to mobile services. Since the mobile services are in a much more difficult reception situation due to poor antennas and motion that results in doppler shifts, this shift of capacity is not a zero sum game. Every b/s of end capacity used for mobile reception will divert more than 1 b/s from home DTV reception. Thus having bought a new big DTV receiver, you may find that the number of b/s available from "free TV", hence picture quality, will decrease as broadcasters go after a new market using spectrum they didn't pay for to compete against others who paid for spectrum. (If broadcasters directly sell services to viewers, then they must split the income with Uncle Same per existing legislation.)

While this technology can be introduced without any additional FCC action due to the deregulatory nature of FCC technical regulation these days, it is likely that the broadcasting establishment will use this as a justification to get even more protection for their signals and limit spectrum options for others.

NY Times coverage