Iterative Decoding of Convolutionally Encoded Multiple Descriptions

In this work, we attempt to capitalize more fully on the source residual redundancy and then develop an MD-ISCD scheme which permits to exchange between its two constituent decoders the whole symbol extrinsic information. The first step toward realization is to derive the modified BCJR algorithm based on sectionalized code trellises that provides reliability information on each transmitted symbol rather than on index-bits. To further reduce the computation, we also apply the concept of Jacobian logarithm to formulate the algorithm in the logarithmic domain.