Title :
Performance of an 8/9 rate matched spectral null code on the PR4 magnetic recording channel
Author :
She, Sian ; Bliss, William G. ; Reed, David E.
Author_Institution :
Cirrus Logic Inc., Broomfield, CO, USA
fDate :
7/1/1998 12:00:00 AM
Abstract :
The performance of an 8/9 rate matched spectral null (MSN) code is analyzed on the PR4 magnetic recording channel with additive white Gaussian noise (AWGN) at the sensor. The high rate is achieved with a fixed charge constraint code of block length N=27 on each of the PR4 channel´s dicode interleaves. A simplified semi-analytic method for MSN codes that approximates the constants multiplying the Q function for certain error event types is introduced and validated by simulations. The 8/9 rate MSN/PR4 system was compared to a normal 16/17 rate code with PR4 and EPR4 detectors for a range of user densities. The MSN/PR4 system has less than 0.9 dB net coding gain for user densities above 2.25, and it´s inferior to simple EPR4 at user densities above 1.9
Keywords :
Gaussian noise; interleaved codes; magnetic recording; partial response channels; trellis codes; white noise; 8/9 rate matched spectral null code; PR4 magnetic recording channel; Q function; additive white Gaussian noise; block length; dicode interleaves; error event types; fixed charge constraint code; semi-analytic method; user densities; AWGN; Additive white noise; Convolutional codes; Costs; Detectors; Logic; Magnetic analysis; Magnetic recording; Performance analysis; Redundancy;
Journal_Title :
Magnetics, IEEE Transactions on
