A signal detection technique using LDPC decoder as channel decoder over recording channels

This paper introduces a signal detection technique using a low-density parity-check (LDPC) code over precoded partial response (PR) recording channels. Under a PR channel considered, the detection scheme can be realized through (1) the design of a precoder that a level detection is available and (2) the modification of the likelihood function (LF) for a sum-product algorithm. A LDPC decoder plays a role as a channel decoder and configures turbo-like systems with the concatenation of outer codes. Besides, the application of the scheme into conventional turbo-like system achieves the performance improvement irrespective of recording densities.