Performance comparison of detection methods in magneto-optical disc system with (1, 7) RLL code

The performance of detection methods is analyzed in the magneto-optical disc (MOD) system with (1,7) runlength limited (RLL) code. The peak detection, threshold detection, and partial response channel with maximum likelihood (PRML) detection are considered. The MOD system uses an SHG green laser and has a storage capacity of 4.2 Gbyte. The channel model is based on the implemented MOD system. The bit error probabilities of each detection method are obtained from simulation for three cases of only media noise, only electronic noise, and a mixture of media and electronic noise. It is shown that the PRML detection and threshold detection achieve a much smaller bit error probability than peak detection and have a similar bit error probability if the SNR is large