From Component SNR to System SFR

A methodology that enables the projection of system performance from component characteristics is presented in this study. Equalized signal-to-noise ratio (eSNR), which refers to the SNR seen by the sequence detector, is a metric that can link component parametrics to Viterbi BER. Orthogonal breakdown of eSNR into contributions from head noise, transition noise, remanence noise, nonlinear distortion and adjacent track interference allows all the disturbances to be weighted properly at the system level. Sector-based BER together with the channel transfer function can further project sector failure rate up to the maximum number of low density parity check iterations without stressing the recording condition. Anticipated system performance from component improvement is readily predictable based on this approach.

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