Public TV’s engineers are divided on question of reopening the three-year-old U.S. standard for DTV transmission, a course of action championed by Sinclair Broadcast Group and now festering on the body technological.
“I’m conflicted — it’s a thing that an engineer doesn’t like to be,” admits Bruce Jacobs, chief technology officer at KTCA in Twin Cities. “We like to have answers.”
The outcome of FCC decisions quite likely won’t hinge on public TV’s position on the matter, of course, but so far the pubcasters have not taken a unified position on the question. If necessary, the system will develop a position through the APTS Engineering Advisory Committee, according to APTS and PBS officials.
And public TV is not rushing to take a position, because its own ranks are divided. A number of prominent station engineers and managers now favor opening up the standard for revision, or at least doing formal tests. Public TV, in particular, has a lot at stake if the chosen DTV transmission technology fails to work without rooftop antennas or cable. This would not only hurt low-income viewers, but also, as Jacobs points out, hurt public TV’s position in bargaining for cable carriage of its DTV services.
In December, PBS did not get a consensus of station reps on its New Technologies Committee for sticking with the standard. “PBS’s silence is read as support for Sinclair,” said PBS Senior Vice President Ed Caleca told the group. “We do not support the Sinclair position.”
The station chief engineers on the separate PBS Engineering Committee are also divided. “We weren’t happy with the results of what Sinclair has done, but we weren’t convinced, on the other hand, that 8-VSB couldn’t be fixed,” says Chairman Jack Wells, of KLRU in Austin.
The adopted standard for modulating the DTV signal is 8-VSB (“Eight Vestigial Side Band”), and the alternative is a newer technology used in Europe, COFDM (“Coded Orthogonal Frequency Domain Multiplexing”).
Sinclair, now owner of 59 commercial TV stations, demonstrated in a Baltimore field test last year that receivers using the U.S. standard, 8-VSB, have a tough time getting a good picture with indoor antennas. Sinclair and a dozen other station groups petitioned the FCC in October to let U.S. broadcasters use COFDM as an alternative.
The debate has now escalated to dueling demos for Washington policymakers. Late in January, Zenith Electronics Corp., inventor of 8-VSB, showed off a series of simulations indicating that newer DTV receivers using the U.S. standard are better at overcoming various kinds of interference than either COFDM or their own first-generation models. The same simulation was shown at the Consumer Electronics Show in Las Vegas early in the month.
Then, last week, Sinclair set up a test at the House of Representatives, challenging all comers to try to get a decent picture from the five operating DTV stations in town, using a variety of indoor antennas. “In six-and-a-half hours, there was not a single DTV station that provided solid reception,” says Mark Hyman, Sinclair’s v.p. of corporate relations.
Most broadcasters can only speculate about how fairly these demos test the opposing systems. Even for engineers, the technology has become so complex and rare that they can’t go out and test it themselves, says Bruce Jacobs.
It might be best to take a couple of years right now to test the systems before many DTV receivers are sold, says David MacCarn, a WGBH technologist. “If we had to change things, it wouldn’t make such a big deal.”
Stay the course
At the PBS New Technologies Committee meeting in December, PBS’s Ed Caleca warned that there’s no such thing as a brief moratorium for testing.
“It’s naïve to say this could be resolved in three months,” he said. After test design, testing and public comments, the process would take 18 months to two years, he predicted. Broadcasters “can’t afford that delay,” he said, because competing DBS and cable operators will be expanding their digital offerings in the meantime.
Caleca says the manufacturers of 8-VSB receivers continue to deliver on promised improvements. “We like what we’ve seen,” he says. “We’re cautiously optimistic that a lot of issues that were raised will become non-issues.”
“Stay the course,” is the recommendation from Richard Wiley, the former FCC chairman who chaired the industry group that proposed the standard adopted by the FCC in 1996. Wiley and other stalwarts spoke to policymakers and reporters at Zenith’s series of demos in January.
Accepting the Sinclair petition will create chaos, predicted Mark Richer, the former PBS engineering chief who recently began a second stint as executive director of Advanced Television Systems Committee. “We would change standards each time someone has a different business model that they think is better.”
You’ll be sorry later
COFDM wasn’t fully considered as an option for the United States in the early 1990s because hardware wasn’t available for testing at the time the industry was putting together the U.S. standard, says Harvey Arnold, a longtime public TV engineer now at Sinclair. “We had not choice but to vote against it,” says Arnold. He would vote differently now.
U.S. broadcasters liked 8-VSB because it could match the reach of their analog TV stations at a low power level — the FCC’s all-important goal for “replication” of coverage areas — and 8-VSB is also about twice as power efficient as COFDM, Arnold acknowledges. “But that advantage is lost when you have any type of channel impairment,” he adds. If the FCC accepted Sinclair’s petition, giving DTV broadcasters the option of choosing either modulation scheme, receivers could be designed to receive either kind of signal. Receiver manufacturers could adapt their products by adding an additional chip that costs just $18, says Mark Hyman of Sinclair.
Broadcasters could choose the technology suitable for local conditions. Stations in the open land around Lubbock, Tex., could use 8-VSB, which would give them the greatest reach and the lowest power, says Jack Wells of KLRU, while a broadcaster in Baltimore, like Sinclair, could use COFDM.
Dennis Haarsager, chairman of the PBS New Technologies Committee and g.m.of KWSU in Pullman, Wash., likes COFDM’s suitability to portable receivers.
“The mistake we’re making is that we’re considering this an engineering question,” says Haarsager, “and we should be considering this a business question.”
If American broadcasters were asking for a system to show HDTV pictures and to replicate the reach of their analog transmitters, 8-VSB might be as good an answer as any, Haarsager says. “But I’ve become convinced that question is the wrong question. I think we have to reinvent why we should be a wireless medium.”
He expects broadcasters will want to beam all sorts of digital material to little TVs in the back seats of cars, and to Palm Pilots and other portable receivers. “To do that properly, you need an extremely robust system that will operate efficiently with really terrible antennas.”
David Liroff, chief technology officer at Boston’s WGBH, agrees with Haarsager’s hunch that the potenital mobile audience could be an important one.
“The dilemma,” says Liroff, “is that all of us are standing at the same starting line, and nobody has mapped this territory.”
Reported with Karen Everhart
Text of FCC’s letter denying Sinclair petition
Federal Communications Commission Washington, D.C. 20554
Released: February 4, 2000
BY CERTIFIED MAIL, RETURN RECEIPT REQUESTED
Mr. Martin R. Leader Fisher, Wayland, Cooper, Leader & Zaragoza, L.L.P. 2001 Pennsylvania Avenue, N.W. Suite 400 Washington, DC 20006
Dear Mr. Leader:
This letter responds to the Petition for Expedited Rulemaking, dated October 8, 1999, filed by Sinclair Broadcast Group, Inc. This petition requests that the Commission modify its rules to allow broadcasters to transmit Digital Television (DTV) signals using COFDM modulation in addition to the current 8-VSB modulation standard. For the reasons described below, the Commission rejects this Petition.
In its Petition, Sinclair argues that broadcasters will be unable to achieve the goal of NTSC replication with their DTV operations under the current ATSC 8-VSB DTV standard. According to Sinclair, this is because 8-VSB cannot be received reliably today with a simple antenna in a station’s core business area due to complex multipath effects. Sinclair states that a COFDM-based alternative DTV standard will offer viewers ease of reception using simple antennas, and enable broadcasters to provide a variety of fixed, mobile and portable video services and greater capacity for technological improvement. Sinclair further argues that this approach would allow the marketplace to determine the appropriate DTV modulation technology and accelerate the development of DTV. Sinclair in particular requests that the Commission appoint an industry task force that, in 120 days, would be directed to: 1) conduct a study and issue recommendations to the FCC regarding the integration of COFDM technology into the ATSC standard; and 2) conduct rigorous scientific analysis to determine the interference ratios for COFDM into existing NTSC and 8-VSB DTV signals.
On October 14, 1999, the Consumer Electronics Manufacturers Association (CEMA) filed an opposition to Sinclair’s petition and a motion for its immediate dismissal. CEMA argues that the petition fails to assert any valid basis for re-opening the DTV standards proceeding at this late date, and presents only arguments that are repetitive of those previously considered. It states that re-opening the DTV standards proceeding would create uncertainty and benefit only those seeking to delay the transition to digital broadcasting. It argues that the industry recommended 8-VSB modulation standard was selected in an open and scientifically rigorous process that included the relative multipath capabilities of both COFDM and 8-VSB.
On October 29, 1999, Sinclair submitted a reply to CEMA’s opposition filing. Sinclair argues that contrary to CEMA’s assertions, it has provided a compelling and convincing basis for initiating a new rulemaking proceeding on DTV standards. It states that it has raised crucial and previously unrecognized issues relating to ease of DTV reception with simple antennas under dynamic multipath conditions. In addition, several broadcasters have filed letters with the Commission supporting Sinclair’s petition and subsequent filing.
For the reasons set forth below, we do not find that Sinclair’s petition warrants consideration by the Commission. We continue to believe that NTSC service replication is achievable by DTV operations using the 8-VSB standard. We note that field test data taken to date supports this conclusion. Sinclair has presented no persuasive evidence to indicate that NTSC service replication cannot be achieved with the 8-VSB standard.
In the Commission’s Office of Engineering & Technology’s (OET’s) recent DTV Report on COFDM and 8-VSB Performance, OET concluded that both 8-VSB and COFDM have certain advantages and disadvantages. OET did not find that the performance potential of either system was clearly superior in all respects. OET further concluded that the relative benefits of changing the DTV transmission standard to COFDM are unclear and would not outweigh the costs of making such a revision. OET also indicated that it believed that 8-VSB has advantages with regard to data rate, spectrum efficiency and transmitter power requirements. We do not find that Sinclair has presented any valid technical information to refute OET’s assessment of these 8- VSB advantages or to refute the recommendation in its report that the ATSC 8-VSB standard be retained.
In making its decision to adopt the ATSC standard, the Commission stated that a single system standard would ensure that all affected parties, i.e., broadcasters, equipment manufacturers, and the public, have sufficient confidence and certainty to promote the introduction of DTV service. The Commission stated that allowing more than one standard could result in compatibility problems and increase the risk that consumer DTV equipment purchased in one city would not work well in another city; or that a digital television set purchased one year might not work several years later. The Commission found that such results would harm consumers and would make it more difficult to preserve a universally available television service. The Commission also found that having more than one standard could cause consumers and licensees to postpone purchasing DTV equipment, because they would not wish to take the risk of investing in what may soon be an obsolete technology, or because they believe better technologies would soon be available. The Commission stated that this could slow investment and, thereby, slow the transition to DTV.
Sinclair has presented no persuasive evidence in its petition and related filings to convince us that the interests of broadcasters, equipment manufacturers and consumers would not be harmed under its alternative standards approach or that conditions have changed to make such an alternative standards approach appropriate at this time. We are concerned that allowing the use of an alternative DTV modulation method as Sinclair proposes would lead to the adverse situations identified by the Commission in the Fourth Report and Order. Further, contrary to Sinclair’s claims, we believe that granting its request would lead to significant delay in the implementation and provision of DTV services to the public. For example, under the Sinclair proposal, the task force would have to develop a complete COFDM standard and achieve industry consensus on that standard. There are, however, a number of different COFDM approaches, such as DVB in Europe and ISDB in Japan. In addition, even if only the European DVB systems were considered, there are a number of implementation options, such as modulation, code rate, and guard interval, that would have to be decided. In addition, laboratory and field testing would likely be needed to develop appropriate interference criteria. We therefore believe that Sinclair’s suggestion that this matter could be addressed and resolved by an industry task force within 120 days is unrealistic and that it is much more likely that this approach would result in a multi-year effort, as argued by CEMA in its filing.
Finally, although Sinclair presents evidence that certain first generation 8-VSB receivers may not operate satisfactorily in strong multipath conditions using simple indoor antennas, we believe that Sinclair has done no more than to demonstrate a shortcoming of early DTV receiver implementation, rather than a basic flaw in the ATSC standard or an indication that service replication is unachievable. We note that OET’s recent DTV Report found that reasonable solutions to the indoor reception and multipath interference issues raised by Sinclair are being developed and are expected to be available in the near future. Information from a number of DTV receiver chip-set manufacturers, such as, Motorola, NextWave Communications, Inc., Thomson Consumer Electronics, and others, indicates that manufacturers are aware of these problems and are aggressively taking steps to resolve the multipath handling limitations exhibited in some first-generation DTV receivers.
While we dismiss this petition, we recognize the importance of the issues raised therein. We believe, however, that the issue of the adequacy of the standard is more appropriately addressed in the context of our review of the entire DTV transition. In adopting the DTV standard in 1997, we stated that “regular reviews of the progress of DTV are highly desirable” and that we would conduct a biennial review of the digital transition to ensure that the introduction of DTV and the recovery of spectrum at the end of the transition “fully serves the public interest.” Among other things, we said we would address “any new issues raised by technological developments, necessary alterations in our rules, or other change necessitated by unforeseen circumstances [including issues related to DTV receiver designs and set labeling].”
In that proceeding, we will be able to consider together all of the issues related to the digital transition, including the progress being made to improve indoor DTV reception under the existing DTV transmission standard and manufacturers’ efforts to implement DTV receiver design improvements. Therefore, within 30 days, we will commence our biennial review of the digital transition and, as a part of that proceeding, will encourage parties to comment on the DTV standard.
Finally, although we are dismissing its petition, we wish to commend Sinclair for its leadership efforts in identifying certain DTV receiver performance concerns and for providing information and data that will be useful to consumer electronics manufacturers in building receivers that meet the expectations of broadcasters and consumers.
Accordingly, pursuant to Section 1.401(e) of the Commission’s Rules, the Petition for Expedited Rulemaking submitted by Sinclair Broadcast Group, Inc., dated October 8, 1999, is hereby denied.
This letter was adopted by the Commission on February 3, 2000.
BY DIRECTION OF THE COMMISSION
Magalie Roman Salas
See Letter from Broad Comm Inc. dated October 18, 1999; Letter from California Oregon Broadcasting, Inc. dated October 27, 1999; Letter from Dominion Broadcasting, Inc. dated November 2, 1999; Letter from Duhamel Broadcasting Enterprises dated October 26, 1999; Letter from Equity Broadcasting Corporation dated October 12, 1999; Letter from GOCOM Communications, L.L.C. dated October 26, 1999; Letter from Grant Broadcasting Group dated November 4, 1999; Letter from National Minority Television, Inc. dated October 29, 1999; Letter from Total Living Network dated November 3, 1999; Letter from Washington State University dated October 18, 1999; Letter from WTLW TV dated November 5, 1999.
See Preliminary DTV Field Test Results and Their Effects on VSB Receiver Design, Gary Sgrigndi, Zenith Electronics Corporation (Preliminary ICCE ’99 Conference Paper). DTV field tests have also been performed by others in nine cities: Cincinnati, OH; Charlotte, NC; Chicago, IL; Dallas, TX; New York, NY; Raleigh, NC; San Jose, CA; Seattle, WA and Washington, DC.
DTV Report on COFDM and 8-VSB Performance, FCC/OET 99-2 (dated September 30, 1999).
We also observe that the relative merits of COFDM were considered by the Commission’s Advisory Committee on Advanced Television Service (ACATS) in the development of the ATSC DTV standard. The ACATS recognized the advantages of COFDM’s multipath handling abilities, but on balance concluded that COFDM would not be superior to 8-VSB for DTV operation in the United States. See Report of the Certification Experts Group, ACATS, August 8, 1995, at page 4; see also Trip Report and Recommendation Regarding COFDM, Task Force on COFDM of the ACATS Transmission Expert Group, January 1994.
Fourth Report and Order, Advanced Television Systems and Their Impact on the Existing Television Broadcast Services, 11 FCC Rcd 17771, 17787-17791 (1996).
Fifth Report and Order, Advanced Television Systems and Their Impact on Existing Television Broadcast Services, 12 FCC Rcd. 12809, 12856-7 (1997). Id.
Federal Communications Commission FCC 00-35
Web page posted Feb. 24, 2000
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public TV and radio in the United States