Re: [WM]: ECC for Koch algorithm

["Dr Johann A. Briffa" <jabrif@eng.um.edu.mt>]

Fuat Demir wrote:
> I am using Koch algorihm in DCT domain for my thesis, but i need an 
> error correcting method. My first detector test results are not good 
> enough.  I will use the algorithm later in MPEG-4, therefor i want to 
> use a quite good ecc.  Could anybody please advice me, which kind of 
> error correcting code shall I use for my program???

It all depends on the error rate you currently have, on the proportion of data bits you can sacrifice, whether you need to use soft
or hard decision decoding, etc. A good answer to this question can't be written in a short email.

If your current error rate isn't too bad (as your message seems to indicate), a simple BCH code may be enough [assuming you intend
to use hard decision]. For better correction, RS codes, turbo codes, LDPC codes can be constructed according to your needs. For
example, with soft-decision decoding, turbo codes that get a BER of 10^-5 at around 0.2-0.3dB SNR (for Gaussian channel) can be
easily obtained at a code rate of 1/4. This is just to give you a figure of merit.

Take a look at Lin & Costello's classic text on ECC - it's a good start.
Hope this helps you along...
Johann

--
________________________________________________________________________
Dr. Johann A. Briffa                    http://www.eng.um.edu.mt/~jabrif
Communications and Computer Engineering            Phone: +356 2340-2078
University of Malta, Msida MSD 06, Malta           Fax:   +356 2134-3577


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