Patent ID: 6904555

Claim:
A decoding apparatus for decoding parallel concatenated coded data comprising: soft output decoding means of a plurality of stages for performing decoding processing repeatedly; means for comparing data which is decoded this time with data which is decoded previous time, both of which are decoded in the repetitive decoding processing; means for detecting error of resulting decoded data using error detecting codes; means for finally judging whether or not error is generated in accordance with output data from the error-detecting means and output data from the comparing means; wherein the means for comparing data obtains the number of discordant sign bits by comparing sign bits of this time with sign bits of previous time, the sign bits being included in output data from the last stage of the soft output decoding means of the plural stages, and wherein if the number of discordant sign bits is larger than a predetermined value, the means for finally judging determines that there was an error generated even though the error detection result shows that no error was generated.