Urban renewal

It was all supposed to be over soon. As America celebrated the arrival of 2007 in Times Square, potentially millions of televisions would go dark at the stroke of midnight when more than 1000 full-power NTSC transmitters were turned off forever. Instead, the nation's full-powered broadcasters will be celebrating yet another year of milking that old NTSC cash cow, flush with more than $1.5 billion in political advertising revenues from the midterm elections.

Last month in this column, I suggested that there might be a lot of old televisions sitting on the curb when the NTSC plug is finally pulled on Feb. 17, 2009. But this may not be the case.

While full-powered broadcasters are a decade into the DTV transition, the nation's Class A and LPTV broadcasters are just starting the process. And viewers in many markets, especially those in the more densely populated areas, may still receive NTSC broadcasts from these stations long after the full-powered NTSC transmitters go offline.

Earlier this year, the FCC announced DTV transition rules for Class A, LPTV and translator licensees, and opened an application window for new digital licenses. The new rules provide that existing permittees and licensees in these services be given the flexibility to choose one of two methods to convert existing analog stations to digital. Stations can either implement an on-channel digital conversion of their analog channel (a flash cut) or seek a (second) digital companion channel that may be operated simultaneously with their analog channel.

According to the FCC order, analog licensees are not guaranteed a digital companion channel and must identify a channel that can be operated consistently with the commission's interference protection rules. The order went on to say that at a date to be determined in the future, the commission will require that the permittee or licensee terminate analog operation, return one of the two channels to the commission and operate the station only in digital mode.

In recent months, the FCC began processing thousands of applications for digital Class A, LPTV and translator licenses. The agency is expected to begin issuing these licenses in 2007.

After these licenses are issued, licensees will have three years to commence digital operations. Thus, low-power NTSC broadcasts will continue for an indefinite period, perhaps lasting well into the next decade.

Do nothing

The demise of full-powered NTSC broadcasts has been viewed as a short-term opportunity for some in the low-power segment of the industry. As the only analog game in town, Class A and LPTV stations will continue to serve the large, installed base of NTSC receivers.

Some licensees have suggested that the low-power service could carry analog versions of the signals of full-powered DTV broadcasters. But this point of view has not gained much industry support.

Many Class A licensees have been acquiring multiple licenses in major markets in hopes that these licenses will become more valuable through the use of digital broadcasting techniques. The most obvious benefit is the ability to deliver multicasts.

With multiple licenses, it would be possible to offer a multichannel service without subscription fees. Many LPTV operators have been developing carriage arrangements with content providers who cannot get clearance via cable or broadcast stations. The proponents of a rapid transition to digital broadcasting techniques are also interested in the ability to deliver new services using IP multicast techniques.

The Community Broadcasters Association (CBA), which represents Class A and LPTV broadcasters, has been highly proactive in lobbying for and promoting the transition to digital for its members. The organization's official Web site works under the banner of DTVNow.org.

The CBA has been lobbying the FCC to grant Class A and LPTV licensees greater flexibility in the technologies used with these new digital licenses. There is strong interest in the A-VSB proposals now being developed and tested by the ATSC. With A-VSB, it might be possible to serve portable and mobile receivers, and to create single-frequency networks to expand market coverage.

It is important to note that operation at lower power levels is not as large a disadvantage with DTV as it is with analog broadcasts. Many full-power broadcasters have been operating their DTV transmitters at reduced power levels with good results. And early ATSC receivers often suffered from overload in the analog front ends when in the presence of high power levels. At power levels around 15kW, a LPTV broadcaster may be able to cover 85 percent of the market area of a high-power broadcaster.

The prospect of building single-frequency networks offers Class A and LPTV stations the potential to be highly competitive in terms of the ability to receive over-the-air broadcasts. If portability and mobility were enabled, entirely new markets could be developed.

Also noteworthy is the FCC's authorization for DVB modulation techniques in spectrum that is being recovered from analog broadcasters. Companies such as Aloha Partners and Qualcomm are developing mobile TV services by using OFDM modulation in the 700MHz spectrum that was acquired at auction.

The CBA is asking the FCC if it too can have the flexibility to choose an alternative to ATSC modulation. At the same time, the CBA is asking the NTIA to consider the possibility of an upgrade path for the digital-to-analog converter boxes for which the agency will be issuing $40 subsidy coupons.

A-VSB developments

Members of the CBA have noted A-VSB's potential to add value to the digital LPTV franchise. The ATSC is in the process of testing and standardizing A-VSB. Several elements of the backward-compatible A-VSB proposals will make it possible to improve reception for fixed receivers using low complexity antennas and to enable walkabout portability and possibly mobile reception.

The A-VSB proponents — Rohde & Schwarz and Samsung, with support from the Sinclair Broadcast Group — recently tested these techniques in the Buffalo, NY, market. They were able to achieve solid reception at speeds up to 80mph.

Further testing is currently underway at the Communications Research Centre in Ottawa. It is anticipated that the ATSC will complete standardization of some elements of the A-VSB proposals in 2007.

As with the digital video broadcast system, improved robustness, portability and mobility come with a price. In a presentation by the A-VSB proponents at the Iowa DTV Symposium held in October, showed one example that trading 5Mb/s of the 19.2Mb/s 8-VSB payload added training signals for advanced equalizers to deliver a robust 1.5Mb/s bit stream.

There are many variables in the proposal. At this point, it is not clear what the actual tradeoffs will be or how A-VSB will compare with DVB-H.

What is clear is that the future may be filled with opportunities for a segment of the OTA broadcast industry that has struggled to compete with full-powered broadcasters. Given the high price that spectrum is bringing at auction, Class A and LPTV licenses may well be worth more than the paper they're printed on.

According to Greg Herman, president of WatchTV in Portland, OR, and vice-president of the CBA, this is an important time for Class A and LPTV licensees to stay the course. He says, “How do you stay in the game? Go digital!”

Craig Birkmaier is a technology consultant at Pcube Labs, and he hosts and moderates the OpenDTV forum.

FRAME GRAB
A look at the issues driving today's technology

DVR penetration in the United States
DVR installations have been steadily increasing Dates Percent of total households with a DVR Percent of total persons 18-49 with a DVR May 1-7, 2006 5.5% 7.3% July 10-16, 2006 7.2% 9.3% Sept. 25 - Oct. 1, 2006 8.9% 11.5% Source: Nielsen Media Researchwww.nielsenmedia.com

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