Clock frequency synchronization for magnetic recording device

An apparatus comprising:

• circuitry configured to generate timing data based on a clock signal and a waveform produced by a head operated with respect to a magnetic rotating recording medium and the clock signal, the rotating recording medium comprising multiple servo wedges arranged on multiple tracks, wherein the timing data comprises information based on a measurement of clock pulses of the clock signal between two servo wedges as indicated by the waveform;
• controller circuitry configured to determine model parameters based on the timing data to model deterministic disturbances associated with the rotating recording medium, determine a first frequency offset based on one or more of the model parameters to predict and compensate for one or more of the deterministic disturbances in an area of the rotating recording medium situated between two servo wedges, and determine a second frequency offset to compensate for one or more nondeterministic disturbances in the area;
• circuitry configured to determine a clock adjustment based on the first frequency offset and the second frequency offset;
• and
• circuitry configured to adjust a clock frequency based on the clock adjustment.

A system comprising:

• a magnetic rotatable recording medium that includes multiple servo wedges arranged on multiple tracks;
• a drive head to read and write data to the rotatable recording medium;
• a motor to rotate the rotatable recording medium;
• a time stamp circuit configured to generate timing data based on a clock signal and a waveform produced by the drive head operated with respect to the rotatable recording medium and the clock signal, wherein the timing data comprises information based on a measurement of clock pulses of the clock signal between two servo wedges as indicated by the waveform;
• a controller configured to determine model parameters based on the timing data to model deterministic disturbances associated with the rotatable recording medium, determine a first frequency offset based on one or more of the model parameters to predict and compensate for one or more of the deterministic disturbances in an area of the rotatable recording medium situated between two servo wedges, and determine a second frequency offset to compensate for one or more nondeterministic disturbances in the area;
• a frequency adjustment calculator configured to determine a clock adjustment based on the first frequency offset and the second frequency offset;
• and
• circuitry configured to adjust a clock frequency based on the clock adjustment.