DTV Transition Picks Up Speed
December 28, 2004
Few people expect the DTV transition to be completed and analog shut off by the original December 2006 deadline, but there seems to be a consensus that it will be completed within the next five years. While many broadcasters feel the transition is moving too fast, considering the small number of DTV tuners in viewers' homes, companies that won use of the out-of-core frequencies in auctions (see "Small Screen TV" for one planned use of these channels) and public safety agencies desperate for more spectrum complain it is not moving fast enough. Indeed, stations on channels 63, 64, 68 and 69, which have been allocated for public safety use, and on adjacent channels that could interfere with systems on these frequencies, could be forced off these channels as soon as Jan. 1, 2008.
The FCC is expected to consider setting a new date for the end of analog broadcasting early in 2005. While it doesn't appear the requirement that 85 percent of households have the ability to receive DTV broadcasts before analog is shut down will be changed, there will be considerable debate over how cable and satellite coverage of DTV broadcasts should be counted towards it.
The FCC has started the process to finalize the stations' DTV channels after analog broadcasting ceases and channels 52-69 are released for other uses. Based on some preliminary studies I've done, I believe this process will be more complicated than many stations expect, especially for stations with out of core DTV channels. The reason is that DTV can co-exist very nicely with co-channel and adjacent channel analog stations. However, due to the broadband, noise-like nature of DTV signals, much higher desired to undesired (D/U) ratios are required between co-channel and adjacent channel DTV stations. Stations expecting to return their analog channel in densely populated areas are likely to find that they cannot replicate their current DTV coverage area on their analog channel without causing interference above the 0.1 percent threshold allowed by the FCC during the channel election process. See my RF Technology columns in TV Technology for examples of channel congestion in the northeast. If all goes as planned, the final DTV Table should be completed in early 2006.
ATSC DTV tuners are dropping in price and improving in quality. DTV set-top boxes, with SD and HD outputs, are now available for under $200 at Wal-Mart. As the FCC DTV tuner mandate starts to affect popular screen size TV sets, we should see more DTV tuners in homes. Zenith's "fifth generation" ATSC tuner has received rave reviews, even from former 8-VSB cynics. Other manufacturers are announcing improved 8-VSB chip sets and I expect we'll see comparable performance from other manufacturers in 2005. I'd also like to see some competition in the market for portable, USB 2.0-based DTV tuners. The only one I've seen to date is the SASEM OnAir USB HDTV. The device places some severe hardware demands on the computer it's attached to. There have been rumors ATI will market a USB 2.0 HDTV tuner/decoder based on its Nxtwave 8VSB chips, but their Web site only shows a PCI based HDTV Wonder card.
Transmitter manufacturers saw a surge in orders as many broadcasters rush to meet the July 2005 deadline for building out DTV facilities to either maximum power, if they are staying on their DTV channel, or to 100 percent replication of their 1998 analog coverage if they are not. The FCC requirement that all DTV stations transmit full PSIP data in compliance with ATSC Standard A65b and provide EIA-708 closed captioning on their DTV signal is driving orders for electronic program guide and closed captioning equipment.
This combination of better and less expensive consumer ATSC receivers and higher power stations operating in compliance with ATSC standards should improve DTV viewer interest and satisfaction.
Several countries announced plans this year to start terrestrial DTV broadcasting while countries that have already begun DTV broadcasting planned for the shutdown of analog TV. At least in one country, the transition to all digital terrestrial TV looks like it may take longer than expected. OFCOM, the telecommunications regulator in the United Kingdom, is now looking at a 2012 date for completing the transition, two years after the previous 2010 target. The United Kingdom is looking at a phased transition, starting in 2007, which will gradually switch off analog broadcasts. So far, the idea of a staged analog shutdown has received little attention in the U.S. It could, however, perhaps provide a way for the FCC to clear the most valuable spectrum in heavily populated areas while giving stations in more rural areas more time to make the switch.