On Sun, Sep 2, 2012 at 12:56 AM, Steve Underwood <[email protected]> wrote: > On 09/01/2012 09:17 PM, Rick Muething wrote: >> Dave has done a good job of squeezing down the bits so it >> may be a reasonable approximation that they are all now of "equal" >> importance. >> > Whilst an accurate statement in terms of producing an intelligible > result, it is highly misleading in terms of the effect of each bit at > the ear. A short loud bang may not affect overall intelligibility very > much, but the cellular FEC bit allocations put a very high priority on > preventing them. Just look at how much they protect the MSB of the > energy fields, whilst pretty much ignoring an error in the LSB of the > same fields.
I think the gray code is already being used to minimize the audible effect of a single bit error. But if we use stronger FEC on some bits than others, it may be advantageous to go back to 2s-compliment and protect the MSBs more. If gray code continues to be used, it may be helpful to use a Hamming distance greater than one where the codes roll from the greatest to the smallest value. That way a single bit error (post FEC) can't cause a big change in value. Steve -- Steve Strobel Link Communications, Inc. 1035 Cerise Rd Billings, MT 59101-7378 (406) 245-5002 ext 102 (406) 245-4889 (fax) WWW: http://www.link-comm.com MailTo:[email protected] ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Freetel-codec2 mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/freetel-codec2
