What if analog sets could receive DTV?

Mar 12, 2001  •  Post A Comment

The controversy over digital television has elicited input from far beyond the usual suspects-TV networks and stations, the cable and satellite industries, consumer electronics manufacturers and movie studios-to include congressional grandstanders and even Harry Shearer, who’s written about it for the Industry Standard. Now Los Alamos National Laboratories is weighing in with a contribution of its own.
A scientist there, George Nickel, has come up with a new modulation scheme for a digital signal that he said enables it to be received on analog receivers. The scheme, he believes, would also save broadcasters from having to set up two antennas and towers and use two separate channels.
“It’s possible to form a digital signal that looks like analog,” Mr. Nickel said. “You have to use pulse amplitude modulation [the “non-return to zero” variety], which produces a truly digital signal [that also] looks like a signal that an NTSC receiver wants to get.”
An old analog NTSC TV receiver would display a picture with “snow bars” instead of the black-border letterbox that more advanced 4-inch-by-3-inch receivers would get from a 16 inch-by-9 inch image coming down the digital pike (see image).
To date, Mr. Nickel’s research has been simulated in a computer at Los Alamos. He decided to work on this DTV research project because he found it a lot like the statistical mechanics he was accustomed to in his specialty, hydrodynamic instabilities. He also thought it might save the TV industry and federal government from redundancies in bandwidth.
His dream, he said, is to have one or two industry groups complete the testing. He has convinced his peers at the New Mexico think tank that he’s on to something. But his work has drawn skepticism and outright hate mail from folks in the TV industry.
“I was unprepared for the scorn I’ve received from several channels,” said Mr. Nickel, who has been a physicist for 40 years. The fallout reminds him of the turbulence that recently surrounded a colleague of his, Wen Ho Lee, who was accused of espionage.
One of the more acerbic responses was from the Consumer Electronics Association, which warned that Mr. Nickel’s ideas would delay the DTV rollout and, by association, disrupt sales of new TV sets.
Mark Richer, executive director at the Advanced Television Systems Committee-which establishes voluntary technical standards for advanced television systems-was more balanced in his feedback.
“From a compression standpoint, it may be interesting,” Mr. Richer said. “But I don’t think it will be very successful in being approved by the FCC as a supplement to DTV if it extends the life of analog television. The goal is to get rid of analog television because it’s an inefficient use of the spectrum.”
On the other hand, Mr. Richer thought that Mr. Nickel’s ideas might be useful for other things, such as datacasting.
“Everybody welcomes Los Alamos bringing their technology forward, but we have to look at more practical applications of the technology, not what they’ve proposed,” he said.
The FCC had similar comments.
“We’re way beyond where Mr. Nickel’s research is-it’s something we should have considered 10 years ago when we were setting the standard up,” said Bruce Franca, deputy chief, office of engineering and technology for the FCC. “We moved away from there due to the desires of the broadcasters and equipment manufacturers. I’m not saying that there are no other applications for the technology. However, for digital television, everybody has decided that the current DTV standard is the way to proceed.”