AMPLITUDE MARGIN ANALYSIS IN HIGH-DENSITY DISK RECORDING USING A PSEUDORANDOM SEQUENCE

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