Digital Communications: Convolutional Codes

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.
Still don't get it? Have questions relating to this topic or others? Suggestions for other problems you'd like to see us do? Post in the comments below or email us at "[e-mail]

[@marceloescamilla8867]

my teacher tried to explain this topic in two hours, didn't understand anything. This vidao makes it so clear.

[@spencerbrown4624]

This makes sense!....Because you explain each step logically and clearly....Also explaining via an example helps rather than mathematically for a general case.

[@saintgersh]

awesome video. Made me understand the jumble of trellis diagram very well. Thanks man.

[@user-jk2ql1tg3r]

Hi just a little question. Is there some reason the initial states you listed them as 00 10 01 11(0 2 1 3), cause I think if you list them as 00 01 10 11 (0 1 2 3)the flow arrow will not such complex.

[@hichamtribak1944]

I have cited your video in my scientific paper. Thank you so much for your explanation.

[@UConnHKN]

Awesome to hear! We would love to read your paper, please email us when it is available to read!

[@inventorofmachines]

Hi. Why did you choose to cite a youtube video instead of, say, a book or a paper? Wouldn't citing a book be easier? Asking to know.

[@shaanhossain6984]

@@inventorofmachines The medium of information is not relevant, it's the quality of information which determines if the source is worth citing

[@imanbagheri1140]

Very helpful, thanks a billion man.

[@mia_in_ch]

still very actual, thanks!

[@Rock57811]

Very nice explanation!

[@arbrakraja9825]

thank you soooooooo much!! thank you

[@Arno18Production]

thank you very much!

[@woodenstick3517]

Can we see something about Turbo codes ?

[@mmtatlas4705]

thank you

[@habbibatomi1465]

Is there an explanation in French

[@supergohanss4]

Please compare your state table against the following state diagram (Fig 8.3) which is correct: web.mit.edu/6.02/www/f2010/handouts/lectures/L8.pdf

[@fataldbz]

i think you have exchanged the convolution codes of state 01 and 11 i.e the codes mentioned in the table for 01 are the codes when the state is 11 and vise versa kindly check

[@UConnHKN]

Hello,
Thanks for your comment. We appreciate everyone who keeps us honest in these videos. If your concern is with the table Zac constructs, I have reviewed it and I see no problem with the numbers that are placed in. Please double check your answer as the conversion from diagram to table can be a bit confusing.
~Andrew

[@imanbagheri1140]

I personally calculate the bot C0 and C1 using simple XOR of S1,In and S0,S1,In ,respectively and there isn't any mistake I think.

[@amichaimazuz6395]

their are mistakes in the state table. for ex: 9:51 from 00, the input is 1, we get 10, and not 11.
another mistake: 10:22, should be 1/11

[@imanbagheri1140]

I just have a question, do you really write reverse, I mean like in the mirror? Isn't it difficult?

[@inventorofmachines]

They flip the video in post-processing

[@erfanshayegani3693]

maaan you made a mistake while filling the table ( states 01,11 corresponding outputs should be reversed )

[@Patrickt1989]

ok cool, so it wasn't just me who thought that

[@Patrickt1989]

disregard, C0 = s1 xor in, and C1 = s1 xor S0 xor in, making the table correct