Source: Audio Week
DTV Backers Press FCC To Dismiss Sinclair Petition
If the FCC seeks comment on the Sinclair Broadcasting bid to allow COFDM modulation for DTV, it would mean ""inevitable"" delay in DTV transition and ""grant them [Sinclair] the remedy they seek"" by delaying DTV deadlines, CEA Vice President of Technology Policy Michael Petricone said. He was among the backers of current DTV standard that participated in demonstrations January 27 in Washington. Demonstration included a prototype of an unannounced 3rd-generation decoder chip from Zenith (3rd-generation chips have been announced by Motorola and NxtWave). Full consideration of COFDM modulation could take ""a number of years,"" said Richard Wiley, who headed the FCC Advisory Committee on Advanced TV Service. Zenith Senior Vice President Richard Lewis said time would be needed because there's no final version of COFDM for use in 6MHz channels. Once a 6MHz version is built it would have to be tested, he said, channel allocation issues would have to be revisited and scarce engineering resources would have to be reallocated from the current system to COFDM: ""If we stop what we're doing and work on a new system, the consumer will be harmed."" Zenith organized a demonstration comparing the performance of the current system and COFDM in an effort to convince FCC and Hill officials to simply dismiss the Sinclair petition. Backers acknowledged that the effort was hurt by the two-day closing of government offices due to snow, leaving only one day for officials to see the demonstration. The demonstration was similar to one Zenith performed at CES, but with additional dynamic multipath and phase noise demonstration, as well as a 3rd-generation Zenith chip. Zenith officials said the chip will be in consumer DTV sets by October and indicated they believe it performs better than 3rd-generation competitors at eliminating ghosts. The chip was developed in partnership with Zenith parent LG Electronics, officials said. ""It's important to differentiate the performance of particular receivers from the capabilities of the standard,"" said Mark Richer, Executive Vice President of Advanced TV Systems Committee. Backers of the current standard, which uses VSB modulation, repeatedly said that second- and thired-generation receivers would solve problems shown in Sinclair demonstrations last year, and that the ability of DTV to receive signals with indoor antennas in downtown environments would continue to improve. Demonstrations, using simulated signals, showed VSB with 5dB better signal-to-noise (S/N) ratio than COFDM, growing to 7dB advantage in presence of large, simple ghosts. Officials said it showed that 3rd-generation chip is 1dB better than 2nd-generation on large ghosts. For multiple, complex, dynamic ghosts, officials said demonstration showed 2nd-generation VSB receivers with 6dB advantage of COFDM, 3rd-generation with 7dB. They said VSB was 20dB better in handling impulse noise and phase noise than COFDM. Sinclair officials immediately downplayed the importance of the demonstrations, saying: ""There are 5 DTV signals in Washington. Why didn't they use one of those for the demonstration? Simulations don't matter; it's the real world that matters.""