Process for transmitting and receiving information bits, wherein a transmitter executes the following steps:
- forming a first binary matrix from the information bits to be transmitted;
- converting the first binary matrix into a second binary matrix by applying a systematic block code corresponding to a product of elementary systematic block codes;
- and
- transmitting bits extracted from the second binary matrix towards a channel, and a receiver executes the following steps:
- forming an input matrix from a signal received according to said channel, the input matrix having the same size as the second binary matrix, and being comprised of digital samples having signs which represent respective initial estimations of the bits in the second binary matrix and absolute values which respectively measure confidences associated with said initial estimations;
- and
- iteratively decoding the input matrix, wherein the iterative decoding of the input matrix includes a number m of decoding cycles, each decoding cycle successively comprising code word search steps for each elementary block code used in the product code, wherein, at each code word search step, a data matrix and a decision matrix having binary components are received which, before the first search step of the iterative decoding are respectively constituted by the input matrix and by a matrix having binary components which respectively correspond to the signs of the input matrix samples, and a new decision matrix and a new data matrix are produced for the following search step, whereby the new decision matrix has binary components which represent new respective estimations of the bits of the second binary matrix and the new data matrix has samples having absolute values which respectively measure confidences associated with said new estimations, wherein decoded information bits are extracted from the decision matrix produced during the last code word search step, wherein each code word search step includes a division of the data matrix received into data vectors each corresponding to a code word of the elementary code and a corresponding division of the decision matrix received into decision vectors and soft decision elementary decodings to respectively process at least certain data vector/decision vector pairs, wherein a set of Y bits respectively having Y specified positions in the second binary matrix are not transmitted towards the channel, and wherein the receiver places in the input matrix, in positions corresponding to said Y specified positions of the second binary matrix, samples having absolute values which are representative of a minimum confidence.