Interlaced Magnetic Recording

Abstract

In this paper, an alternative magnetic recording architecture and corresponding signal processing schemes are presented, named interlaced magnetic recording (IMR). Tracks are recorded in an interlaced manner with different linear densities, which provides favorable tradeoff between areal density capability (ADC) and update-in-place write overhead. By predefining the recording order, tracks are under either double-sided squeeze or non-squeeze, and average ADC can be optimized by differentiating the linear density. Numerical evaluations with a micro-pixelated magnetic channel model show the ADC gain of IMR over conventional perpendicular magnetic recording (PMR), while manageable rewrite overhead compared with the shingled magnetic recording (SMR). For example, IMR provides 4.21% higher ADC over PMR near 1 Tb/in2 channel density scenario, while requires at most 1 rewrite overhead, negligible compared with the typical update overhead in SMR. Writing and reading of IMR can be efficiently managed by aggregating interlaced tracks as sub-zones and switching the channel configurations.