Sensitivity of PRML systems to timing offsets

Abstract

An effective distance measure based on the state metrics of a Viterbi algorithm detector (VAD) is defined and used to estimate the sensitivity of a VAD to constant timing offset. It is shown that the statistics of this measure contain sufficient information to estimate the performance of a maximum likelihood sequence detector with additive white Gaussian noise. The statistics are used to determine the timing windows for various binary and ternary partial response systems. Additionally, it is shown that the statistics can be used to generate probability of error versus SNR curves for various timing offset values.