Automatic gain control and timing recovery on the partial-response maximum-likelihood recording channel

An advanced technique of signal processing for digital magnetic recording is referred to as the partial-response maximum-likelihood (PRML) channel. In a partial-response maximum-likelihood system, Cideciyan et al. propose a digital gradient algorithm to track variations of gain and timing phase. In this work, we investigated a simpler digital gradient algorithm for gain and timing recovery control loops. It is shown that this algorithm can perform as well as the one presented by Cideciyan et al., but with simpler hardware implementation and less signal processing delay.