Abstract: A method is provided for transmitting a digital signal between at least two transmitters and at least one receiver, using a concatenation of at least two codes. The method includes a first encoding step, in the transmitters, which outputs at least two first code words; a first transmission step of the first code words, via at least two distinct transmission channels; a receiving step, in at least one relay device, of at least two of the first code words, known as intermediate code words; a step of intertwining at least one part of the bits of the intermediate code words that outputs the intertwined bits; a second step of encoding the intertwined bits, in the relay(s), which outputs at least one second code word, taking into consideration the intermediate code words; a second step of transmitting the second code word(s) through the relay device(s), so as to enable, in the receiver(s), an iterative decoding, taking into account the first code words, and then a redundancy formed by the second code word(s).

Abstract: A wireless communication system constructed by a MIMO antenna system and transmitting information from a transmitter having Nt number of transmitting antennas to a receiver 3 having Nr number of receiving antennas. The receiver 3 of this wireless communication system 1 linking the inputs and outputs between a demodulating unit 32 demodulating the input signals from receiving antennas 31 and a decoding unit 35 receiving as input that demodulation output and decoding the non-binary LDPC code of the GF(q) one-to-one under predetermined conditions to enable the inputs and outputs of this demodulating unit 32 and decoding unit 35 to be directly connected and thereby improve the decoding characteristic. That predetermined condition is preferably q=2Nt·m.

Abstract: A parity check matrix construction method for constructing a non-binary parity check matrix defining a non-binary LDPC code. In particular, a parity check matrix construction method for setting codewords able to stably give a superior decoding performance is provided. For this reason, the non-binary non-zero elements are selected so that the determinants of the partial matrices corresponding to the cycles in the parity check matrix do not become 0. Due to this, a non-binary parity check matrix able to give large weight codewords is constructed.

Abstract: A method is provided for transmitting a digital signal between at least two transmitters and at least one receiver, using a concatenation of at least two codes. The method includes a first encoding step, in the transmitters, which outputs at least two first code words; a first transmission step of the first code words, via at least two distinct transmission channels; a receiving step, in at least one relay device, of at least two of the first code words, known as intermediate code words; a step of intertwining at least one part of the bits of the intermediate code words that outputs the intertwined bits; a second step of encoding the intertwined bits, in the relay(s), which outputs at least one second code word, taking into consideration the intermediate code words; a second step of transmitting the second code word(s) through the relay device(s), so as to enable, in the receiver(s), an iterative decoding, taking into account the first code words, and then a redundancy formed by the second code word(s).

Abstract: A wireless communication system constructed by a MIMO antenna system and transmitting information from a transmitter having Nt number of transmitting antennas to a receiver 3 having Nr number of receiving antennas. The receiver 3 of this wireless communication system 1 linking the inputs and outputs between a demodulating unit 32 demodulating the input signals from receiving antennas 31 and a decoding unit 35 receiving as input that demodulation output and decoding the non-binary LDPC code of the GF(q) one-to-one under predetermined conditions to enable the inputs and outputs of this demodulating unit 32 and decoding unit 35 to be directly connected and thereby improve the decoding characteristic. That predetermined condition is preferably q=2Nt·m.

Abstract: A parity check matrix construction method for constructing a non-binary parity check matrix defining a non-binary LDPC code. In particular, a parity check matrix construction method for setting codewords able to stably give a superior decoding performance is provided. For this reason, the non-binary non-zero elements are selected so that the determinants of the partial matrices corresponding to the cycles in the parity check matrix do not become 0. Due to this, a non-binary parity check matrix able to give large weight codewords is constructed.

Abstract: A decoder of LDPC codewords using the iterative belief propagation algorithm stores a posteriori information on variables. An updating device updates the a posteriori information on variables, and a first computation device computes variables to constrain messages from a posteriori information on variables and variable to constraint messages from previous iteration. A second computation device computes a constraint to variable messages from variable to constraint messages computed by the first computation device. A further computation device updates the a posteriori information on variables. A shuffle device transfers the a posteriori information on variables to the first computation device, and a further shuffle device transfers information from the second computation device to the storing device. The decoder further includes a device for compression-storage-decompression of the constraint to variable messages. The disclosure also relates to a corresponding method, computer program and system.

Abstract: A decoder of LDPC codewords on GF(rq), using the iterative belief propagation algorithm comprises at least storing means to store a posteriori information on variables. Updating means updates the a posteriori information on variables, and computation means computes variables to constrain messages from a posteriori information on variables and variable to constraint messages from previous iteration. Computation means computes a constraint to variable messages from variable to constraint messages computed by the first computation means. Computation means updates the a posteriori information on variables. Shuffle means transfers the a posteriori information on variables to the first computation means, and shuffle means transfers information from the second computation means to the storing means. Compression-storage-decompression means constraint to variable messages. In one form, the invention concerns also corresponding method, computer program and system.