Fcc Begins Dab Rulemaking

Television Digest with Consumer Electronics, Nov 8, 1999

Saying it wasn't deciding in favor of in-band, on-channel (IBOC) version of digital audio broadcasting (DAB), FCC opened DAB rulemaking. Significant portion of rulemaking was devoted to seeking comment on whether DAB systems using new spectrum, possibly including TV Ch. 6, would be more efficient use of spectrum. Commission also asked how DAB could be implemented to provide more opportunities for low-power FM (LPFM) and other new entrants.

Broadcasters didn't immediately react publicly to rulemaking, although one official said that they were "not pleased with some items in the proposal," including LPFM and possible use of TV channel. However, he said, "on balance, we're pleased that this new technology is moving forward." Asked about potential impact of policy decisions such as LPFM on DAB rulemaking, Lucent Digital Radio Pres. Suren Pai said: "I certainly hope the policy issues will not cloud this discussion."

DAB system proponents generally were pleased that FCC started rulemaking, although not necessarily with all of its details. Pai said process "at least gets the ball rolling," but he would have preferred stronger support for IBOC, which he said is best for "seamless transition." New spectrum approach is easier technologically, Pai said, but could be more expensive for consumers and broadcasters. "It's clear that IBOC is the preferred solution" by FCC, Pai said, "and as long as we can deliver a good system, I don't think anybody will stand in our way."

"This notice should not be construed as the start of an IBOC rulemaking," FCC said (MM 99-325), although it later noted preference for IBOC system. It said it agreed with NPR that "at this time it is not possible to definitely settle this issue in favor of IBOC." Among other things, Commission asked whether there were tradeoffs to allow in-band operation that would hurt long-term future of DAB, and whether new spectrum would be better.

Notice seeks comment on compatibility of DAB and LPFM and asks how DAB could be designed to protect future LPFM service. It notes that DAB technology, for example, appears not to rely on protection from 3rd adjacent channel interference, so it might not affect LPFM. Rulemaking asks whether advances in receiver technology provide additional protection against interference, potentially allowing "more intensive spectrum utilization."

On issue of new spectrum, rulemaking suggests that Ch. 6 (82- 88 MHz) could be possibility, particularly after DTV transition. Although 57 TV stations are using Ch. 6 now, only one (New Haven) is assigned DTV Ch. 6 and FCC said it believes that station could be reassigned. Rulemaking notes, however, that DTV transition may not be complete for years, delaying DAB use of that spectrum. FCC also asks whether other spectrum would be better for DAB and whether, if Ch. 6 were assigned for radio, LPFM licensees should get preference.

FCC tentatively concluded it should have role in setting DAB standard, but asked many questions on what that role should be. It asked whether it could facilitate industry-set de facto standard, rather than using time-consuming govt. process. Commission said it would be "premature" to commit to particular process for selecting best technology, but suggested process coordinated by National Radio System Committee (NRSC) might be best. Pai, whose Lucent had raised questions about NRSC testing process, said he believed NRSC testing process now is better and he was encouraged that FCC would intervene if process didn't work.

USA Digital Radio (USADR) CEO Robert Struble said his company was "absolutely ecstatic" about rulemaking. He said Commission "embraced much of what we had asked for" in petition, including technical and commercial "criteria" by which competitive IBOC systems should be judged. Struble said his "read" of document is that if IBOC technology proves as viable as proponents such as USADR have claimed, endorsing IBOC would be "an easy decision" for FCC. He also praised Commission for "tacitly endorsing" NRSC IBOC evaluation process and said FCC "went further than we expected" in expressing interest in evaluating IBOC test results itself. He said that because terrestrial DAB couldn't be commercialized in Ch. 6 spectrum before 2007 "at the earliest," viable IBOC buildout would make those alternatives "nonissue."

Other tentative conclusions on which FCC seeks comment include: (1) Whether FCC should regulate auxiliary services of DAB broadcasters similar to those for analog broadcasters, as long as they technically don't impair DAB reception. (2) Whether it's necessary to give AM and FM equal signal quality in DAB, since AM service with only FM quality would be improvement. (3) Whether public interest would be best served by DAB channel assignment policy that would allow DAB stations to serve current analog protected service contours, rather than current coverage areas.

Among remaining questions in rulemaking: (1) Whether compatibility with analog signals should be evaluative criterion. Text said USA Digital Radio could interfere with existing analog broadcasts. (2) Whether DAB broadcasters should get permanent access to full bandwidth now included in emission masks, effectively doubling bandwidth from that of AM and FM, or whether additional spectrum must be returned at end of transition. (3) What are minimum power levels for DAB.