SOMEWHERE OUT THEREYou might not have noticed that you can catch more flies with honey than with vinegar. First, however, I'd like to submit a little note about the style of this month's offering.
If I don't seem quite myself (whoever I - or we - may be), it's because I'm not. I've asked someone with a greater command of language to edit me this month so that I may be understood this time even by William Kennard, himself. Yes, I think I have something very important to say. First, however, I would like to pose a question.
Suppose a rocket ship is carrying through the vacuum of outer space a TV technologist, the Easter Bunny, the inventor of the perfect digital transmission system and Godzilla (or Gojira, for those of you who prefer to transliterate Japanese more traditionally). Now suppose the rocket ship is hit by a meteor and has explosive decompression before anyone can put on a spacesuit. Who dies?
The answer is obviously the TV technologist (which is why you won't find me on a rocket ship anytime soon). Why? The other three don't exist.
Please consider the last sentence carefully. Godzilla doesn't exist. The Easter Bunny doesn't exist. Finally, the inventor of the perfect digital transmission system doesn't exist. Why not? That's easy. It's because the perfect digital transmission system doesn't exist. No one, therefore, could have invented it.
Here is that key point once again. The perfect digital transmission system does not exist. I don't care whether you're talking about QPSK or B3ZS or QAM or IEEE-1394. Every digital transmission system has flaws.
Most have their good points, but they all have flaws. At some point, under some conditions, each and every digital transmission system will fail. Have I made myself clear enough? Perhaps I haven't. Please allow me to get a little more specific.
The digital transmission system developed by Zenith, submitted by the Grand Alliance, approved by the Advanced Television Systems Committee (ATSC), and adopted by the Federal Communications Commission (FCC) as the U.S. digital television method of transmission, eight-level vestigial-sideband (8-VSB) is - how shall I put this delicately? - imperfect. It is flawed. It is not divine (and I am not intentionally forcing a comparison here with the old Scandinavian-developed DTV system, HD-DIVINE).
That is not terrible. The European Digital Video Broadcasting Group's DVB-T terrestrial transmission system, based on coded orthogonal frequency-division multiplexing (COFDM) of QAM carriers is also imperfect. So is Japan's ISDB. Again, there is no such thing as a perfect digital transmission system.
ANALOG VS. DIGITAL
Of course, there's no such thing as a perfect analog transmission system, either. Under bad conditions, unfortunately, analog transmission systems usually outperform digital. That's because analog systems do not suffer from a "cliff effect," and digital systems do.
Under perfect conditions (which also don't exist), analog beats digital, because digital must have quantization error. Under slightly less than perfect conditions, digital beats analog. Analog will have degraded slightly, digital will not.
As conditions get worse and worse, analog transmission results also get worse and worse, while digital doesn't change. At some point, however, the digital system's error-correction capability can't keep up with the worsening conditions, and the system fails. At that point, without improving one iota - indeed, as the results continue to degrade - analog suddenly leaps ahead of digital and stays ahead until things have gotten so bad that a viewer decides the horribly degraded pictures and sounds are no better than their absence.
That is why analog television works. It's also why many people use cable TV, satellite, MMDS, OVS, VDSL or other alternatives to analog television transmission.
Another alternative to analog television transmission - indeed, an alternative pushed by the Federal government - is DTV. Cable TV has flaws. Analog and digital satellite systems have flaws. MMDS, OVS, VDSL and all the rest have flaws, too. Anyone could easily expect, therefore, that DTV would have flaws, too.
DTV, however, was set an impossible task for any digital transmission system. It was to duplicate analog television coverage.
That concludes the technical summary. Here comes the political part.
Last summer, Sinclair Broadcast Group conducted some tests in Baltimore. The tests showed that, for the receivers used, the transmitter site and parameters, and the receive sites where tests were made, COFDM outperformed 8-VSB. I believe it to be a consensus of opinion that the reason COFDM outperformed 8-VSB was that the bulk of the sites, in urban areas, were subject to multipath interference. The tests were extensively witnessed, and participants were given opportunities to choose their own sites.
As a result of that testing, Sinclair prepared to submit a petition to the FCC regarding DTV transmission. At that moment, two companies, Motorola and NxtWave, announced advanced equalizing 8-VSB processors that would, it was said, make multipath interference a thing of the past. Sinclair withheld its petition, pending the results of its testing of the Motorola and NxtWave chips. When it became apparent that it would not get the opportunity to test the new chips, Sinclair submitted its petition anyway, and it quickly garnered the support of hundreds of broadcasters.
In essence, the petition says that, if a broadcaster can prove non-interference, it should be allowed to transmit DTV as COFDM instead of 8-VSB. Opponents of the petition say it seeks to delay DTV, but Sinclair specifically says that the FCC's implementation schedule should not be changed. Opponents say it will delay DTV, for who would buy a DTV receiver not knowing if it would work with future transmission systems?
Now, it appears that FCC chairman William Kennard succeeded in getting his fellow commissioners to reject Sinclair's petition without even seeking public comment on it. That upsets me.
I used to think 8-VSB was the superior system. I know COFDM is not perfect, either. Recent events, however, have made me not very sanguine about 8-VSB's prospects.
First, there was the field-testing conducted by Motorola and NxtWave. You can find the former on the Internet at mot-sps.com/adc/MCT2100test.html. To put it in a nutshell, both companies found receive sites and 8-VSB stations that worked. Both also found sites and stations that didn't. Motorola didn't pull any punches in its reports, noting that the failures were caused by multipath, the characteristic that COFDM is very good at dealing with.
Then came some published testing in New York City, at different sites, with a range of witnesses. Sinclair didn't participate in these tests, but they were still pretty damning to 8-VSB.
Then came Kennard's speech at the Consumer Electronics Show in January, picked up by many news outlets. He was upset that DTV receivers aren't yet cable-compatible.
Now let me see if I have this straight. Sinclair's petition is bad because consumers will be afraid to buy boxes that might not work in the future, but there's nothing wrong with the chairman of the FCC announcing from newspapers nationwide that today's DTV boxes might not work in the future due to cable incompatibility. Yes, strange as it seems, I think I've got it right.
It's not only cable incompatibility. The receivers lack conditional access capability, copy protection, a data-applications interface to allow them to do the things everyone says DTV is supposed to do, and a host of other features, ranging from EIA-708 closed-caption decoding to the ability to receive descriptive audio for the visually impaired. Furthermore, even if a station transmits 8-VSB and a decoder successfully receives it, that decoder might not create any pictures if the broadcaster, in full accordance with FCC rules, transmits a video format not appearing in the ATSC's infamous Table 3 (as KCOP in Los Angeles has done).
Ignore all that, however, and there's still a fundamental problem with the rejection of the Sinclair petition. The petition doesn't call for any broadcaster to transmit COFDM. It doesn't call for any receiver manufacturer to produce any COFDM receivers. It would seem, therefore, to give 8-VSB an overwhelming advantage.
There are now (as this is being written), depending on how one counts, between 88 and 120 full-power 8-VSB broadcasters on the air. As of the end of last year, the Consumer Electronics Association claimed more than 130,000 "digital televisions" sold to dealers. Motorola and NxtWave are preparing their second-generation 8-VSB chips, and Oren has joined them. Compare that with no U.S. COFDM broadcasters and no COFDM receivers sold in the United States.
THE BETTER STANDARD
That brings me back to the opening line of this month's column. If 8-VSB is, in fact, better than COFDM, then all the acrimony and confusion caused by the Sinclair petition could have easily been eliminated by simply approving it. There would have been no more debates. There would have been no threatened lawsuits. There would have been no lobbying of congressional caucuses devoted to urban areas.
If 8-VSB is, in fact, better than COFDM, then the easiest way to put this sordid period behind us would have been to approve the petition. Sinclair would have then won a Pyrrhic victory. They could have enjoyed winning the battle but losing the war.
Yes, if 8-VSB is the superior transmission system, there was absolutely no reason not to approve the petition and get Sinclair out of our hair once and for all. Of course, if I had a vested interest in 8-VSB and was worried that it was not the better of the two, I'd fight the Sinclair petition tooth and nail. I'd risk the Congressional lobbying, court battles and bad publicity. I'd have to. The head start that 8-VSB has could disappear once it was shown that COFDM was superior. Oh, yes, I would definitely fight the Sinclair petition if I had a vested interest in 8-VSB but knew or feared COFDM was superior.
Because everyone opposed to the Sinclair petition says 8-VSB is superior, however, there's no reason to create a fuss. We all should have welcomed the Sinclair petition with open arms (by which I do not mean "brandishing an unconcealed weapon").
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