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Old March 28th 09, 01:57 PM posted to rec.radio.amateur.antenna
[email protected] jimlux@earthlink.net is offline
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First recorded activity by RadioBanter: Jan 2007
Posts: 61
Default Noise figure paradox

On Mar 26, 9:35*am, "Joel Koltner"
wrote:
Hi Jim,

"Jim Lux" wrote in message

...

Actually, state of the art is probably Low Density Parity Check (LDPC)
codes, as far as approaching the limit.


I hadn't heard of them; thanks for the link. *Can you comment on how they
compare to Reed-Solomon codes?

I have just enough background in error-correcting codes to spout off the right
keywords in nearly-coherent Usenet posts and wait for people to point out my
errors. :-)


Much longer block length than typical R-S. Also, the way the check
bits are generated is different. Each check bit isn't formed by
combining ALL the source bits, just some of them (obviously a
different "some" for each of the check bits), hence the name Low
Density. Both are usually roughly rate 1/2.