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From: robert@wiliki.eng.hawaii.edu (Robert Morelos-Zaragoza)
Newsgroups: sci.electronics
Subject: Re: Information, channel capacity, and feedback
Message-ID: <10961@uhccux.uhcc.Hawaii.Edu>
Date: 15 Jan 91 01:02:00 GMT
References: <27992@cs.yale.edu> <81035@sgi.sgi.com>
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Reply-To: robert@wiliki.UUCP (Robert Morelos-Zaragoza)
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The capacity of a Gaussian channel with feedback can at most double,
as shown by Professor Thomas Cover and his students at Stanford
University. But the fact that feedback does not improve the capacity
much remains to be shown matematically.

You may write to Prof. Cover to find out the status of this
research problem. His address is

Prof. Thomas M. Cover
Durand Bldg., Rm. 121
Department of Electrical Engineering
Stanford University
Stanford, CA 94305


By the way, this is an excellent question. It is not covered by almost
all communications or coding theory books, which only discuss technical
methods of using feedback. So it is worthless to look into the books
for the answer. This is a question whose answer is a good research problem,
for a Ph.D. dissertation for instance.

Aloha,

Robert Morelos-Zaragoza
Department of Electrical Engineering
University of Hawaii
2540 Dole Street #483
Honolulu, HI 96822