Final ThoughtThe Queen’s Digital Television

Once upon a time, the Federal Communications Commission began an inquiry into how best to deliver HDTV to U.S. households. About three years into the inquiry, digital transmission appeared to be the way to go, and by the time the rules were issued, after 10 years, digital terrestrial television (DTT) transmission was a requirement. HDTV wasn’t even mentioned.

Strange as it may seem, it’s true. There is not a single law, rule, or regulation requiring any U.S. broadcaster to deliver any amount of HDTV at any time.

Nevertheless, most U.S. digital television broadcasters are transmitting at least some HDTV, and all U.S. digital television receivers are capable of receiving those HDTV signals. There are costs associated with those HDTV transmissions.

Broadcasters must, in general, pay for high-level MPEG-2 encoders, instead of the main-level models they could use if they were never going to carry HDTV. And consumers must pay for an MPEG-2 decoder capable of dealing with HDTV and for format conversion to convert any ATSC format into something useful to individual displays, which can range from ordinary TV sets to HDTV plasma panels.

With the possibility of HDTV making its way from a DTT receiver to the Internet, program providers want still more circuitry in those receivers—circuitry that can act on withheld retransmission consent and also protect against unauthorized copying. That costs money, too.

Perhaps as a result of the costs, or perhaps as a result of reception problems and marketing failures, a grand total of just 542,659 ATSC DTT receivers left factories between the time the FCC issued its DTT rules in 1997 and the end of last year. If every single one of those ended up in a home (which was clearly not the case), that would represent just about one half of 1% of U.S. television households.

The United Kingdom is a much smaller place than the United States. Nevertheless, in just four months, about half a million DTT receivers were sold there. Why the great disparity between the countries?

Some people, no doubt, would point to the difference in transmission systems. In the U.S., we use ATSC’s 8-VSB; the U.K. uses DVB-T’s COFDM.

There have certainly been some reception problems with 8-VSB, but there have been some reception problems with COFDM, too. In fact, shortly before the four-month period of stunning sales began in the U.K., some DTT broadcasters opted to shed capacity in favor of more robust transmission.

If they want to transmit HDTV, U.S. broadcasters don’t have the same option. Yes, capacity shedding schemes to allow more robust ATSC transmission have also been proposed here, but the reduced data rates are insufficient for MPEG-2 coding of HDTV.

Then there’s cost. The list price of standalone U.K. DTT receivers is about $150. Those in the U.S. are typically closer to $500.

Again, HDTV is a factor. The U.K. receivers cannot deal with HDTV. Their transmission-reception front ends are very flexible, which is how they could handle the change to more robust transmission, but they deal with just one standard definition format. Their decoders are less expensive, and they need no format conversion.

Without HDTV, consumers clearly aren’t buying U.K. DTT receivers for added picture detail. They do get the benefits of ghost- and snow-free digital transmission. And they get many more channels of broadcast programming than were previously available. It’s like cable TV without a monthly fee.

This doesn’t appear to be an anomaly associated only with the U.K. In Berlin, DTT receivers cost about the same as those in the U.K., and sales went even faster—70,000 in a few months in just that one German city—enough to allow all of the commercial analog transmissions to cease by the end of February of this year. Again, no HDTV is offered. Instead, viewers get 22 channels of programming with no monthly cable fee.

In the U.S., there have been calls in Congress to force broadcasters to carry HDTV, and there have been calls in Congress to force the DTT transition to be complete by the end of 2006. Maybe they should make up their minds.

Mark Schubin is an engineering consultant with a diverse range of clients, from the Metropolitan Opera to Sesame Workshop.