Hard-decision decoding
(step 1)


Fig. 1 Example illustrating the Viterbi algorithm. The labels on the branches indicate branch metrics; cumulative metrics of surviving paths are given in frames.


Figure 1 shows the Viterbi decoding proces. The received code sequence 10 10 00 00 01 11. An encoded data sequence 1 0 1 1 with appended tail 0 0 is transmitted. Receiver knows the length of the information sequence and it knows that the tail of two zeros is appended to the information sequence. The purpose of a tail is to terminate the encoding process in state zero. Two zeros of the tail enter the encoder in the last two steps of encoding.


Please, verify the example with our Viterbi Algorithm Applet