Digital Communications: Viterbi Algorithm

Graduate Student Zac Sutton of Uconn HKN explains how to encode a data stream using a convolutional encoder and how to decode the received sequence using the Viterbi Algorithm.

[BS-jwnf]

My savior. Explained in 4 hours worth of lecture in 26 minutes and way clearer

[wokwithjosh]

Not only is the explanation clear, the way the tables or chart are layout is systematic. I will use this approach for my exams

[negarm]

Every time I need to review the viterbi algorithm, I watch this video. Thanks a lot for this clear explanation.

[rohitvasu]

man !!! thank you !!! this question saved me 20 points in the finals !!! thank you so much for this explanation !!

[johnli]

Exellent! the best I have seen on this topic!

[lucasgameiroborges]

best explanation ive seen, keep up the good work!

[foxtrot]

Is it correct if you pick the other node?

[nyanjomjackonyango]

Thanks alot for this. Simple to understand and straight to the point.

[henriebillz]

Thank you very much. You are a life saver :)

[ferhatvarolgunes]

man this is most clear explanation that i saw too far thanks for making it so simple, appreciated man thanks a lot.

[klodious]

the question is, probably the stream length is unknown so when we implement the viterbi algorithm do we implement the digital design when we reach a certain size so only then it returns the best path with the least hamming distance or not? and if so how could I determine the appropriate ram size.

[Skordaki]

Thank you very much. Very good teacher.

[WistrelChianti]

Thanks very much, really clear explanation and I appreciate you saw the process through fully (satisfying for the learner and the extra practice is no bad thing). Any idea what a multi convolutional encoder is? Applying a convolutional encoder more than once? (i.e. encoding the output of the original encoding) or something else?

[jshiva]

Thanks a lot for the patient and beautiful explanation

[PETAJOULE]

Nice demonstration of viterbi algorithm which is used in convolutional decoding.

[saintgersh]

Excellent explanations. Why didn't I see this video before my exam??

[t.chumpuwiset]

excuse me sir, can you show me in case that considering 2D 3x3 matrix? they call it 64 state but i think it should be 512 state for that (8x8x8)

[amadiraq]

Thank you very much man, you really made it look so easy.

[hichamtribak]

love your work. great explanation. Good continuation professor. The initial code word is 00110, so what is the first input bit to be injected into the encoder, if we want to do reverse encoding? i.e from 00110 to the corresponding encoded message. is it the far right 0 or the far left 0?

[steverok]

That is one cool drawing board. 15 minutes in, and we are only four information bit intervals into a 4-state trellis. Wouldn't a top-down derivation from theory into a generic algorithm be a better way to teach it ? In practice, soft decisions can be much more powerful, especially in non-uniform channels. In that case, it is no longer Hamming distance. There are other nuances like pruning the initial and final stages. In the end, a simulation model measuring performance versus complexity, with and without various algorithm features, is, ultimately, invaluable in making design trade-offs. Anyway, sorry, don't even know the audience here. Love this stuff. Just happy to see that classic communication theory hasn't gone out of style.