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Design >> High-Speed I/O Design >> Why we need Viterbi Decoder in High speed link?
https://designers-guide.org/forum/YaBB.pl?num=1110800747

Message started by raymond_luo2003 on Mar 14^th, 2005, 3:45am

Title: Why we need Viterbi Decoder in High speed link?
Post by raymond_luo2003 on Mar 14^th, 2005, 3:45am

Dear all,

I am doing high speed SerDes stuff for 1394B PHY. Currently I am reading a lots of paper, and trying to draft my Serdes architecture for this PHY.

I got very much confused there is a few of papers mentioning about the Viterbi Decoder, which seems to help receiver of SerDes improving the jitter performance.

Anyone can help me to understand it a little more?

Thanks in advance!
Raymond

Title: Re: Why we need Viterbi Decoder in High speed link
Post by DReynolds on Mar 24^th, 2005, 8:21am

Raymond, Veterbi decoding is nothing more than ordering the data you send in a specific way so that when you try to recover it from a noisy channel (sometimes you will get an answer that is not quite correct), you can more easily decide what the data was because you know leagal and illegal sequences in the data.

David Reynolds

Title: Re: Why we need Viterbi Decoder in High speed link
Post by Danny ONeill on Jun 13^th, 2005, 10:02pm

Raymond: suggest 3rd level engineering course at University level

Title: Re: Why we need Viterbi Decoder in High speed link
Post by raghunath cherukuri on Oct 14^th, 2005, 6:30am

Viterbi decoder is optimal in the Maximum Likelyhood sense.
Viterbi algorithm is used for sequence estimation(not symbol estimation). Viterbi algorithm can be used for decoding as well as detection( detection comes before decoding). It works in the AWGN environments well.
I guess they are using Channel Coding(FEC) in serial links nowadays.. I know LDPC is optional in 10G Ethernet. So please check if FEC is required in your application. Otherwise Viterbi is for just detection only.

Raghunath