INFORMATION DECODING AND ENCODING METHOD,INFORMATION COMMUNICATION METHOD, INFORMATION DECODING DEVICE, TRANSMITTING DEVICE, AND INFORMATION COMMUNICATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To realize reduction in calculation load and improvement in error rate characteristics when decoding a received word acquired by receiving a coded word via a communication path, which is subjected to block encoding. SOLUTION: In a method for decoding the received word which is acquired by receiving the coded word transmitted via the communication path after applying LDPC encoding to an information word added with a CRC code, the method is performed by the steps of producing (100) estimated word X by calculating likelihood of each bit of the estimated word X in accordance with the LLR-BP decoding algorithm, determining (102) whether the estimated word X satisfies a parity check equation or not, producing (106) an estimated word C satisfying the parity check equation by repeating the LDPC encoding using a part of reliable information from the estimated word X based on the likelihood of each bit of the estimated word X in accordance with OSD algorithm when the determination is denied, and repeating error detection (110) using the CRC code to the estimated word C. Then the estimated word C is outputted (112) as an effective estimation result when the estimated word C is determined to have no error (determination of the step 110 is affirmative), and decoding of the received word is terminated. COPYRIGHT: (C)2006,JPO&NCIPI