Timing Recovery in Conjunction With Maximum Likelihood Sequence Detection in the Presence of Intersymbol Interference

A decision-directed timing recovery scheme is discussed that maintains and updates a separate phase estimate path for each survivor data path in the maximum-likelihood (ML) sequence detection of intersymbol interference (ISI) channels. For each survivor path, the phase estimate is updated recursively using symbol-decisions implied in the path. Unlike in the existing per-survivor timing recovery approach, there exists a single global timing loop that operates on a single stream of delayed phase estimate samples released from the merged survivor path or an up-to-date best survivor path. Loop analysis, tracking behavior simulation and BER simulation validate the proposed approach.