Adaptive decoding of convolutional codes

[摘要] Convolutional codes, which are frequently used as error correction codes indigital transmission systems, are generally decoded using the ViterbiDecoder. On the one hand the Viterbi Decoder is an optimum maximum likelihooddecoder, i.e. the most probable transmitted code sequence is obtained. Onthe other hand the mathematical complexity of the algorithm only depends onthe used code, not on the number of transmission errors. To reduce thecomplexity of the decoding process for good transmission conditions, analternative syndrome based decoder is presented. The reduction of complexityis realized by two different approaches, the syndrome zero sequencedeactivation and the path metric equalization. The two approaches enable aneasy adaptation of the decoding complexity for different transmissionconditions, which results in a trade-off between decoding complexity anderror correction performance.

[学科分类] 电子、光学、磁材料