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Mikhail Tsinberg on 8-VSB vs. COFDM: Complexity, Not Theory, Is the Limiting Factor

Dale Cripps · 1999

Mentioned: Mikhail Tsinberg, Dale Cripps, Bill Schreiber

Summary

Toshiba America's Mikhail Tsinberg, drawing on his experience at Philips Labs during Grand Alliance development, argues that 8-VSB has no fundamental theoretical performance ceiling compared to COFDM. He contends that increasing 8-VSB demodulator complexity to match COFDM would yield equivalent performance, and questions whether robust indoor antenna reception is a genuine market requirement.

Originally published at www.ilovehdtv.com/hdtv/tsnberg.html. View in Wayback Machine →

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"During the time that many research groups (including my own at Philips Labs) were competing outside, and then inside of Grand Alliance, to develop the best system -- 8VSB and COFDM were compared on a few occasions.

As I was told by the experts at that time...there fundamentally is no theoretical limit on performance of 8VSB, and it could be identical to COFDM."

Mikhail Tsinberg, Senior Manager, Toshiba America Consumer Products

I wrote the following to Mike. He was kind enough to answer below and let us use his response for a discussions point. It is an important response to keep in mind as we move further down what could be a disruptive course of altering the standard at the FCC.

Dear Mike,

Can you throw any light on this modulation story? Are we just in too early an iteration to draw a sound conclusion, or is there some fundamental reason why this will never get "that much" better...better, yes, but "that" much better to satisfy the market deeply? Any light you can shed (off or on the record) is very welcome.

Dale Cripps

Dale,

During the time that many research groups(including my own at Philips Labs) were competing outside, and then inside of Grand Alliance, to develop the best system - 8-VSB and COFDM were compared on a few occasions.

As I was told by the experts at that time, there fundamentally is no theoretical limit on performance of 8-VSB and it could be identical to COFDM.

Initial complexity is the issue. (The) 8-VSB allows simpler and less expensive implementation for reasonably good outdoor channels or CATV. Remember, more then 60% of Americans watch CATV these days and only 25% are using reception from the air. A really small minority of these 25% use indoor reception. Rest are probably using DBS--that is QPSK in any case.

COFDM could not be scaled for simpler implementation. It is a complex demodulator from start. My understanding, again from the words of some experts, that if you increase complexity of 8-VSB demodulator to be equal of the complexity of COFDM demodulator, their performance will be equal as well. Of course I, and probably nobody else yet, have seen that implemented for obvious reasons: FCC and broadcasters always specified outdoor reception as necessary criteria for DTV. And 8-VSB in its simpler implementation always beat COFDM tests in these channels.

CE industry was always aware of possible use of DTV on CATV and 8-VSB in its simpler implementation works fine in these channels as well. There were no indication then, and I do think even now, that robust indoor reception is a needed requirement. I think 8-VSB is a flexible enough system that if DTV business will demand indoor reception, more complex 8-VSB demodulators will be available on the market. Do broadcasters and FCC need a proof of this now? If they are - we (industry wide) have experienced engineers and laboratories who may be able to construct this kind of prototype.

In my mind the real question is how many Americans are watching TV on indoor antenna today and how many will continue to do so after they purchase $3000 worth of DTV receivers and HDTV monitors tomorrow?

I hope this helps,

Mikhail Tsinberg
Senior Manager
Toshiba America Consumer Products
82 Totowa Road
Wayne, NJ, 07470
E-mail: [email protected]

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Rersponse:

Bill Schreiber