Modified Viterbi algorithm for decoding of block codes

The paper has considered optimal methods for decoding error correction codes which allow increasing reliability of the data transmission across noisy communication channels. The purpose of work is to solve a task to increase efficiency of decoding short block codes. The paper has suggested a very simple modification of the algorithm for decoding quasicyclic block codes built on the basis of short convolutional codes. Besides, decoding is executed by the Viterbi algorithm not taking into account a block structure of the code but decoding an ordinary infinite sequence. The analysis of the suggested decoder characteristics has been performed and complexity of its implementation has been estimated. The paper has shown that by means of the suggested Viterbi decoder for the block codes it is possible to ensure a bit error rate being analogous to the bit error rate for the corresponding convolutional code under the decoding complexity increasing only in 2..3 times.