A proposed decoding scheme for robust error correction in advanced ATSC Systems

This paper describes an advanced decoding scheme for ATSC Systems. To improve the reception under dynamic propagation conditions an advanced VSB (A-VSB) was proposed. One of the new features in this transmission system is the improved performance of forward error correction. To use the full capacity of this redundancy information, an optimum decoding algorithm is essential. Most receivers use a soft-output Viterbi algorithm as convolutional decoding which offers the opportunity of adapting likelihood paths easily. Not only Reed-Solomon corrected packets might be fed back to the Viterbi decoder and can be used as soft-input information. Even transport stream sequences, which appear periodically, could be useful for an optimum convolutional decoder. This paper shows an example, how transport stream information might be used as additional forward error correction. Finally, results of the improvements are shown as bit-error probability in AWGN channel at the convolutional decoders output.