Turbo codes for PR4 and EPR4 magnetic recording

This paper presents further results of the application of turbo codes to magnetic recording channels. A rate 16/17 turbo code has been simulated on both a preceded PR4 and EPR4-equalized Lorentzian channel. Gains of 4.4 dB and 3.9 dB are obtained respectively, thus encouraging continued research in this area where high rate codes are desirable. A rate 13/14 convolutional code has also been applied to a PR4-equalized channel. It results in 1.2 dB less gain than the rate 16/17 turbo code on the same channel and therefore indicates the turbo code parity bit is more powerful in comparison to a convolutional code parity bit.