Concatenated coding and iterative decoding for magnetic and optical recording

Ph.D.Steven W. McLaughli

Precoded PRML, serial concatenation, and iterative (turbo) decoding for digital magnetic recording

We show that a high rate serially concatenated code used in conjunction with a precoded partial response equalized magnetic recording channel and iterative decoding can provide similar performance to a turbo code on the same channel. The precoded partial response maximum-likelihood (PRML) read channel is incorporated as the inner code of the concatenated coding scheme and the outer code is a high rate convolutional code. Gains of 4.8 dB above conventional PRML at a bit error rate of 10 \Gamma5 for a rate 13/14 code can be achieved. Index Terms---Iterative decoding, precoded PRML, serial concatenated codes, turbo codes. I. Introduction Recently [1], [2], [3], have shown that high rate turbo codes [4] can provide 4-6 dB of coding gain when applied to PR4 and EPR4 equalized magnetic recording. In this paper we show that this outstanding performance is achievable without the use of turbo codes per se. That is, we show that a high rate serially concatenated code used in conjunction wi..