Amplitude margin analysis in high density disk recording using a pseudo-random sequence

In a recording system employing a sampling detector such as PRML, amplitude margin is a figure of merit to determine the ultimate bit error rate (BER) performance. Analysis of amplitude margin is useful in allocating the error budget and optimizing the component design. In this study, the amplitude mean square error (MSE) and sequence amplitude margin (SAM) are analyzed through a pseudo-random sequence (PRS) recording. The influence of noise, inter-symbol interference (ISI), nonlinear distortion (NLD), precompensation, and overwrite on the amplitude margin is systematically characterized and investigated. The track edge effect of isotropic and oriented media is also compared and discussed.