Global Timing Control with Applications to Tape Storage Channels

A new approach is introduced for symbol synchronization in multi-channel data storage systems called global timing control (GTC). Applying results from optimum filtering theory to the state-space model of the timing process in multichannel data storage systems, a multi-input multi-output PLL solution is derived. Efficient implementations are developed through simplifications of the optimal solution obtained. The performance of the GTC technique is analyzed using actual read- back waveforms captured in commercial tape drive systems. The results demonstrate the impressive robustness of GTC and its excellent resilience against loss-of-lock phenomena.