# Shannon limit in Eb/N0 for r=1/2

1. Mar 25, 2009

### Wolfson

Hello,

The Shannon limit is Eb/N0=(2^(n)-1)/n where n=2*r

So the Shannon limit for r=1/2 should be Eb/N0=1 and in dB 0dB.
In the literature it is often said to be 0.97869 (0,19dB)!

For example here:
http://www.scribd.com/doc/6983295/eBookturbo-and-Trellis-Coding [Broken]

and here:
http://wicl.kaist.ac.kr/pdf/sychung%20phd%20thesis.pdf" [Broken]

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I also found a hint in one document that the shannon limit is in deed 1 (0dB), but only for Codes of rate 1/2 defined over GF(q) and 0.97869 (0,19dB) for binary Codes
Could anybody explain that to me?

Thanks in advance :),
Wolfson

Last edited by a moderator: May 4, 2017