A statistical analysis of multiple adjacent track writing with track misregistration

We have derived the exact statistical distribution of erasure location from adjacent track on a data track after repetitive writing on the adjacent tracks with track misregistration (TMR). The result is a function of the in-drive TMR distribution and the number of writings. We show that the effect of multiple adjacent track writing is equivalent to a dc squeeze of the data track plus a random write TMR with smaller variation. The reduction of the effective write TMR is significant. However, the squeeze, hence erasure, on the data track increases precipitously with the number of writings. The read-back signal and on-track bit-error rate after multiple adjacent track writings are studied with simulation.