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Error correcting codes

Started by Sharan123 4 weeks ago3 replieslatest reply 3 weeks ago92 views

Hi All,

I would like to know if my understand as given below is correct,

Error correcting codes can be classified into

1) Block codes

Block codes are memory less

2) convolution codes

convolution codes can be further of the following,

1) systematic

2) non-systematic

3) recursive

4) non recursive

5) Multiple combinations of 1,2 with 3,4. E.g. systematic and recursive etc.

Let me know if my understanding, broadly, is correct ...


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Reply by jmarceloldNovember 18, 2019

Yes,

I would add that Block codes can be linear, systematic and cyclic. 

I don't know if non-linear block code are used in practice.

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Reply by SlartibartfastNovember 18, 2019

Kind of, but some of those terms, like "block code" aren't universally defined.  e.g., a "block code" can be a code with a finite-length or fixed-length codeword, like a Reed-Solomon or other algebraic code, but a "block code" can also be implemented with, and often is implemented with, a convolutional code.

Likewise block codes can be systematic, have recursive and non-recursive elements, etc.

I don't know what you mean by "memory less".

It is a broad topic with many paths. 

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Reply by Sharan123November 18, 2019

Thanks.

On memory less coding method:

if a coding method does not involve delays of some sort. It means that output is a function of current inputs and not previous inputs.