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Re: Fade remover



Frederick M. Spinner <fspinner@hotmail.com> wrote:

>You know, the sad thing about this is that is the extra margin
>gained by FEC would have effectively been free.. no cost...
>
>I think they were afraid that the PSK400 modems would be obsolete,
>but that hardly matters now that soundcard modems are out, does it?
>
>Am I correct in assuming that most of the Reed-Solomon and
>Vitribi encoding could be done with lookup tables if necessary?
>I thought that was the case. If so, the "SLOW" COSMAC 1802
>theory goes right out the window...

Reed-Solomon encoding is straightforward. Just use the
generator polynomial directly. Length 255 codes (defined
over GF(256), i.e., bytes) are attractive, since we
tend to encode information in bytes, and microprocessors
can manipulate bytes easily.

Convolutional encoding is just bit-pushing (the Viterbi
algorithm is for decoding only). Nothing to it...

Laura Halliday VE7LDH     "Que les nuages soient notre
Grid: CN89mg                     pied a terre..."
ICBM: 49 15.042 N 122 59.053 W       - Hospital/Shafte
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