Decoding method, decoding apparatus and digital transmission system of product code

A decoding apparatus comprising:

• a demultiplexer for demultiplexing demodulation data and correction information into N1 C2 code demodulation data and N1 C2 code correction information, where N1 is a positive integer;
• N1 C2 code decoders for receiving the N1 C2 code demodulation data and the N1 C2 code correction information demultiplexed by said demultiplexer, for updating the correction information by carrying out soft input/soft output decoding of the C2 code, and for outputting updated correction information and the demodulation data;
• a multiplexer for multiplexing the correction information and the demodulation data output from said N1 C2 code decoders;
• and
• a C1 code decoder for receiving the correction information and demodulation data multiplexed by said multiplexing means, for updating the correction information by carrying out soft input/soft output decoding of the C1 code, and for decoding a binary linear code from the updated correction information and the demodulation data.

A digital transmission system having a transmitter and a receiver, said transmitter including an encoder for converting information data to a product code including a C1 code and C2 code, and a modulator for modulating the product code output from said encoder, and said receiver including a demodulator connected to said transmitter via a transmission medium for demodulating the product code modulated by said modulator of said transmitter, and a decoding apparatus for decoding the product code demodulated by said demodulator, said decoding apparatus of said digital transmission system comprising:

• a demultiplexer for demultiplexing demodulation data and correction information output from said demodulator into N1 C2 code demodulation data and N1 C2 code correction information, where N1 is a positive integer;
• N1 C2 code decoders for receiving the N1 C2 code demodulation data and the N1 C2 code correction information demultiplexed by said demultiplexer, for updating the correction information by carrying out soft input/soft output decoding of the C2 code, and for outputting updated correction information and the demodulation data;
• a multiplexer for multiplexing the correction information and the demodulation data output from said N1 C2 code decoders;
• and
• a C1 code decoder for receiving the correction information and demodulation data multiplexed by said multiplexing means, for updating the correction information by carrying out soft input/soft output decoding of the C1 code, and for decoding a binary linear code from the updated correction information and the demodulation data.