Abstract
Double layer perpendicular recording system has attracted special interest as the next generation recording technique. Although the waveform shape of read-back signal on this system is usually modeled by the integrated form of Lorentian pattern which has been widely adopted in the longitudinal recording system, the validity of this model hasn't been confirmed yet. In this paper, we investigate another model, so called Sigmoid pattern, which has recently been proposed, and compare with conventional model on the linearity to the variation of recording density. The results show that mean square error between experimental data and the calculated waveform by models can be reduced by the new model through wide range recording densities.
