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Reed Solomon: time vs. frequency domain algorithms

Started by lindasel November 7, 2008
These questions refer to a thesis posted on the Internet.
Author: Chih-Lung Shih
Title: Soft IP Generator of Reed Solomon Codec for Communications Systems
Location: National Central University, Taiwan

In Fig. 1.4 there is a chart which lists some algorithms as frequency
domain and others as time domain.  Berlekamp-Massey is classofoed as a
frequency domain algorithm.  The Euclidian algorithm is classified as time
doman.  The Euclidian algorithm is grouped with the Chien search and Forney
equation, but Berlekamp-Massey is not.

Questions:

Does this mean that the Berlekamp Massey and Euclidian algorithms produce
different error locator polynomials and that there is nor one unique error
locator polynomial for the received message?

Is it not valid to use the Berlekamp-Massey algorithm with a Chien search
and the Forney equation?

Thank you for any comments, as my field is primarily audio and speech.


lindasel <lseltzer@alumni.caltech.edu> wrote:

>These questions refer to a thesis posted on the Internet. >Author: Chih-Lung Shih >Title: Soft IP Generator of Reed Solomon Codec for Communications Systems >Location: National Central University, Taiwan > >In Fig. 1.4 there is a chart which lists some algorithms as frequency >domain and others as time domain. Berlekamp-Massey is classofoed as a >frequency domain algorithm. The Euclidian algorithm is classified as time >doman. The Euclidian algorithm is grouped with the Chien search and Forney >equation, but Berlekamp-Massey is not.
Most algebraic coding people do not use the "time domain" vs. "frequency domain" termniology. Steve
> >Most algebraic coding people do not use the "time domain" vs. >"frequency domain" termniology. > >Steve
Is there any reason the Berlekamp-Massey algorithm is not usable with the Forney algorithm? Is there some modification that has to be made to the Berlekamp-Massey algorithm?
>
lindasel <lseltzer@alumni.caltech.edu> wrote:

>Is there any reason the Berlekamp-Massey algorithm is not usable with the >Forney algorithm?
No
>Is there some modification that has to be made to the >Berlekamp-Massey algorithm?
Possibly, as there are several different forumlations of either Berlekamp-Massey and Euclid key-equation-solver algorithms. When you compute the Forney polynomial, you need to do it in the correct way for the particular key equation you are using. Steve