Modeling of PRML timing loop as a Kalman filter

This paper demonstrates the equivalence between the timing loop used in the partial response maximum likelihood (PRML) disk-drive channel and a modified Kalman filter. The Kalman filter is shown to reach a steady-state gain that corresponds to the timing loop when in its steady-state tracking mode. The dependence of the steady-state gain on the noise and physical properties of the loop is investigated. The timing loop is then optimized using the properties of the Kalman filter.