2-D Data-Dependent Media Noise in Shingled Magnetic Recording

This paper investigates 2-D media noise in shingled magnetic recording (SMR) systems. The media noises caused by the overwriting of the next track and the residual information from the previous track are asymmetric in the cross-track (CT) direction and are found to vary with the linear density. The media noise after equalization is found to be 2-D data dependent, with its mean and variance affected by the nonlinear transition shift in the CT and down-track directions, respectively. Also the effect of media noise on the bit error rate (BER) is studied for increased track densities during the writing process. The effect of jitter on the BER is always significant with increased track density in SMR systems, while the effect of overwriting and inter-track interference on the BER performance are quite different for readback with rotated and normally oriented readers, even though the same writer is used during the writing process.