Multi-channel equalization for PWM channels in magneto-optical recording

We show by modeling and simulations that multitrack readback and equalization can lead to significant increases in the track density in magneto-optical recording without performance degradation due to two-dimensional interference, We assume an architecture in which an isolated set of closely spaced tracks is read simultaneously. In an earlier paper, we described a multi-channel zero-forcing equalizer and a two-dimensional decision-feedback equalizer for this architecture, and presented their performance for PPM (pulse position modulation) optical recording channels, Since PWM (pulse width modulation) recording is more popular in magneto-optic (MO) disks, we model the PWM channel in this paper and show simulation results for the performance improvement obtained by using multi-channel equalization for data recorded in PWM format.