Turbo-decoder of turbo code concatenated in series, SCCC, for correcting errors in a word to be decoded comprising: - an input (INPUT) configured to receive the word to be decoded comprising intrinsic information items pertaining to useful data, external and internal redundancy data, - an internal decoder configured to implement a SISO algorithm, carry out a part of the decoding of the word based on the intrinsic information items pertaining to the useful data, and the internal and external redundancy data; and generating internal extrinsic information items based on the external extrinsic information items generated by an external decoder in addition to the intrinsic information items which are provided to it - an external decoder configured to implement a SISO algorithm; carry out another part of the decoding of the word based on the intrinsic information items pertaining to the useful data and the external redundancy data; and generating external extrinsic information items based on the internal extrinsic information items generated by the internal decoder in addition to the intrinsic information items which are provided to it; the internal decoder and the external decoder being configured to receive in parallel the intrinsic information items of the channel pertaining to the word to be decoded at the start of each decoding cycle; the external decoder being configured to start the step of external decoding and produce extrinsic information items based on the intrinsic information items without awaiting the availability of extrinsic information items of the internal decoding step and the internal decoder is configured to start the internal decoding step and produce extrinsic information items based on the intrinsic information items without awaiting the availability of extrinsic information items of the external decoding step. - an input (INPUT) configured to receive the word to be decoded comprising intrinsic information items pertaining to useful data, external and internal redundancy data, - an internal decoder configured to implement a SISO algorithm, carry out a part of the decoding of the word based on the intrinsic information items pertaining to the useful data, and the internal and external redundancy data; and generating internal extrinsic information items based on the external extrinsic information items generated by an external decoder in addition to the intrinsic information items which are provided to it implement a SISO algorithm, carry out a part of the decoding of the word based on the intrinsic information items pertaining to the useful data, and the internal and external redundancy data; and generating internal extrinsic information items based on the external extrinsic information items generated by an external decoder in addition to the intrinsic information items which are provided to it - an external decoder configured to implement a SISO algorithm; carry out another part of the decoding of the word based on the intrinsic information items pertaining to the useful data and the external redundancy data; and generating external extrinsic information items based on the internal extrinsic information items generated by the internal decoder in addition to the intrinsic information items which are provided to it; the internal decoder and the external decoder being configured to receive in parallel the intrinsic information items of the channel pertaining to the word to be decoded at the start of each decoding cycle; the external decoder being configured to start the step of external decoding and produce extrinsic information items based on the intrinsic information items without awaiting the availability of extrinsic information items of the internal decoding step and the internal decoder is configured to start the internal decoding step and produce extrinsic information items based on the intrinsic information items without awaiting the availability of extrinsic information items of the external decoding step. implement a SISO algorithm; carry out another part of the decoding of the word based on the intrinsic information items pertaining to the useful data and the external redundancy data; and generating external extrinsic information items based on the internal extrinsic information items generated by the internal decoder in addition to the intrinsic information items which are provided to it; the internal decoder and the external decoder being configured to receive in parallel the intrinsic information items of the channel pertaining to the word to be decoded at the start of each decoding cycle; the external decoder being configured to start the step of external decoding and produce extrinsic information items based on the intrinsic information items without awaiting the availability of extrinsic information items of the internal decoding step and the internal decoder is configured to start the internal decoding step and produce extrinsic information items based on the intrinsic information items without awaiting the availability of extrinsic information items of the external decoding step.