Patent ID: 7185259

Claim:
A computing apparatus-implemented decoding method of a product code including a binary linear C 1 code with a code length N 1 and an information length K 1 and a binary linear C 2 code with a code length N 2 and an information length K 2 , said decoding method of a product code comprising: a first soft input value generating step of generating a first soft input value by adding a received value of the C 1 code and a predetermined correction value; a first soft output value generating step of generating a first soft output value from the first soft input value generated at the first soft input value generating step, by carrying out soft input/soft output decoding of the C 1 code; a first correction value update step of updating a correction value by subtracting the received value of the C 1 code from the first soft output value generated at the first soft output value generating step to generate an updated correction value equal to the difference between the received value of the C 1 code and the first soft output value; a second soft input value generating step of generating a second soft input value by adding a received value of the C 2 code and the correction value updated at the first correction value update step; a second soft output value generating step of generating a second soft output value from the second soft input value generated at the second soft input value generating step, by carrying out soft input/soft output decoding of the C 2 code; a codeword estimating step of estimating a transmitted codeword from the soft output value generated at the second soft output value generating step; and a second correction value update step of updating the correction value by subtracting the received value of the C 2 code from the second soft output value generated at the second soft output value generating step, wherein the product code is iteratively decoded by inputting the updated correction value to the first soft input value generating step.