A Study of Multitrack Joint 2-D Signal Detection Performance and Implementation Cost for Shingled Magnetic Recording

Abstract

Shingled magnetic recording is a promising option to sustain the historical areal density growth of hard disk drives while retaining conventional heads and media. Nevertheless, highly scaled shingled magnetic recording is subject to severe intertrack interference (ITI), fewer grains per channel bit and therefore lower signal-to-noise ratio (SNR). This naturally demands 2-D read channel signal processing, which has an inherently large spectrum of detection performance versus computational complexity tradeoff. By concurrently detecting multitrack readback signals from a read head array, joint 2-D signal detection can fully utilize the 2-D interference to maximize the detection performance at the penalty of the highest computational complexity. Multitrack joint 2-D detection has not been thoroughly studied from either the detection performance or silicon implementation perspective because of the justifiable concern on its practical feasibility. To fill this missing link, this paper presents a comprehensive study of multitrack joint 2-D signal detection performance and silicon implementation cost. We further present an interleaved pipelining strategy to reduce joint 2-D signal detector silicon consumption. By carrying out comprehensive simulations and application-specific integrated circuit (ASIC) design, this paper shows that multitrack joint 2-D signal detection is a practically attractive option with superior detection performance and affordable silicon cost, especially when considering projected CMOS technology scaling toward 16 nm and below.