TCS Daily

FCC Foists Faulty Digital TV Standard On Consumers

By John Merline - March 5, 2001 12:00 AM

In January, the National Association of Broadcasters released a study that was supposed to help jump-start the faltering transition to digital television. The report claimed to put to rest a largely sub rosa controversy over the digital TV transmission standard picked by the Federal Communications Commission five years ago. It concluded that the existing standard, called 8VSB, was as good as a proposed alternative standard, called COFDM. Almost immediately, the FCC responded saying that as far as it was concerned, the matter was closed.

But don't expect the report's findings to do much to increase consumer demand for digital TVs. Far from it. What the report shows most glaringly, in fact, is how awful the transmission standard with which the FCC has saddled the country. It is only one of many problems plaguing the digital transition, but it is the one that will likely prove most troublesome. Among the study's findings:
  1. Even with 6-foot tall antennas placed outdoors - ideal for capturing a broadcast signal - the testers could only get a picture in fewer than half the sites in the Baltimore/Washington region, and just 28 percent of the sites in the Cleveland area.
  2. Indoor reception was even worse. Using the best indoor antenna available, they could only get a picture in 30 percent of Baltimore/Washington locations, and just 26 percent of those in Cleveland.
In a true understatement, NAB report said the results were "disappointing."

These results confirm what many other studies have found. The digital picture is wonderful when it can be viewed, but in just about every other aspect, the FCC's chosen transmission standard is worse than the good old analogue version it is supposed to replace. Despite state-of-the art receivers, locking on to a digital channel is often difficult, if not impossible. And even when you do, cars driving around outside - or people moving around inside - can easily break up the signal.

This writer experienced these shortcomings firsthand in a demonstration. Getting a digital picture often meant finding precisely the right location for the antenna, pointing it in just the right direction, and repeating these steps each time the channel was changed. Movement around the antenna by cars and people often caused the picture to go blank. My 19-year-old black-and-white RCA TV with a broken antenna is more robust and reliable.

These dismal results come despite repeated promises over the years that such problems would soon get fixed. Back in 1999, the FCC noted indoor reception difficulties with the existing digital standard, but said "improved receivers will be available this fall and ... further improvements will be introduced next year" that would largely fix the trouble. That same year, Robert Graves, chairman of the Advanced Television Systems Committee (which helped develop the U.S. digital TV standards), said, "Improved receivers on the near horizon (are) designed to address the challenges of indoor reception." And at a congressional hearing last summer, NxtWave Communications CEO Matt Miller said that problems with indoor reception "reflect deficiencies in early generation (digital receiver) technology." These technical issues, he said, "have been largely resolved."

Now the same promises are being made in the face of the NAB's findings -- just give us a little more time to get the receivers right. But it's not at all clear when this promise will ever be fulfilled, if ever.

A leaked internal ATSC draft report last July said receiver improvements "are expected to be incremental rather than revolutionary." And a University of Massachusetts study concluded that "it is difficult to envision" a receiver that will work well with the existing transmission standard. The NAB report noted that "the pace at which improved consumer products are reaching the marketplace is disappointing."

So what's wrong with the 8VSB standard that makes it so difficult to receive with ease? Essentially the difficulty stems from something called "multipath." What happens is this: Over-the-air signals get bounced off walls, buildings, trees and moving objects, with each bounced signal arriving at the receiver at different times. With an analog TV, that "multipath" can cause ghost images. Bad enough. But with 8VSB, it can cause a blank screen, as technical aspects of the 8VSB signal make it difficult for it to cope with the multipath confusion. And in the digital world, it is all or nothing.

As is usually the case, consumers know better than regulators. Which is no doubt one key reason why, despite the fact that 187 TV stations now broadcast in digital, 33 million analog TV sets were sold last year, but only about 26,000 digital TV tuners. (Far more digital TV monitors have been sold, mainly to customers who want to watch DVDs. But without a tuner, these TVs can't receive over-the-air broadcasts.) That's a terrible track record for a new technology which otherwise tends to penetrate the market at a much faster rate.

Is there a better transmission standard? There appears to be. Indeed, it duplicates the ease of reception most people have today with traditional analog. And just about every other country on the planet, including all of Europe and most of Asia and Latin America, have picked it. It is the COFDM standard -- the very one the NAB study said was no better than the 8VSB, a conclusion now being challenged by the manufacturers of COFDM equipment. They claim the NAB test misused the receiver equipment, and so got poor results with COFDM.

One good reason foreign nations have picked COFDM is that it has no problem with multipath. In the demonstration this writer attended, a handheld, flat-screen TV picked up a COFDM signal with a pencil-thin antenna while being walked through a bustling downtown train station and driven around down city streets. The picture was not lost once. Even the NAB study noted that "in the 'ease of use-testing' (antenna pointing sensitivity), COFDM outperformed 8VSB." In England, which uses the COFDM transmission standard, 30 percent of viewing homes now are digital, and the country is already making plans to finalize its transition.

But even if COFDM would be a better standard overall for the U.S. - still, admittedly, the subject of heated dispute among experts - the chance that the U.S. would ever make the switch at this point is essentially moot. Broadcasters, who've spent millions converting to the existing standard, along with receiver makers, aren't willing to see their substantial investments go down the tubes. And the FCC is loathe to admit to a costly mistake.

That leaves only one option. And it is that all those promises that the existing standard can be made to work at least as well as today's analog system can be fulfilled. If the transition to digital TV is to have any hope of succeeding, they had better.


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