Combination of decoding of error-correcting codes and equalization for channels with intersymbol interference

AbstractThis paper describes structures and algorithms to carry out combined decoding of an error-correcting code (ECC) and equalization, which can improve the performance in a channel for a noise with intersymbol interference (ISI) over that obtainable with a separate decoder and equalizer. Two types of structures and algorithms for combined decoding and equalization are presented. Equalization can achieve stable adaptation for unknown characteristics or/and variance of a channel by using some information obtained in decoding, while decoding can be modified to adapt to the condition of a channel by exploiting information from equalization. In particular, a method to utilize the reliability of decoded data to minimize the misadjustment and error propagation due to undetected errors and miscorrected data in decoding of an ECC is proposed. Moreover, an adaptive decoding scheme based on the combined decoding and equalization is proposed to detect or correct correlated errors arising from ISI and filtering. It can reduce decoding complexity by using information about the ISI obtained in equalization. Theoretical error probability and simulation results are given to evaluate the system