A New Joint Source Channel Decoding Scheme Based on Speech Signal

The study proposes a joint source channel decoding scheme with the speech source residual redundancy without changing the complexity of the decoding algorithm. As the speech parameter index could be used to calculate the transition probability of the speech coding parameter index, we can get transition matrixes on different speech parameters according to the statistics of the speech signal. Using the transition matrix, we can get new priori information for the channel decoder which will finally lead to a better decoding result. The method updates the priori information for channel decoding before the channel decoding starts, aiming to get a better channel decoding result as well as reducing the iteration times of the decoding process. As shown by the simulating results, the joint source channel decoding scheme can reduce the bit error rate of the channel decoding even under bad channel circumstance.