Apparatus, system, and method for detecting a periodic sequence of servo signals

A computer program product comprising a computer useable medium having a computer readable program, wherein the computer readable program when executed on a computer causes the computer to:

• detect a plurality of values of a periodic sequence;
• confine the plurality of values to a limited set of confined values;
• correlate the confined values with a plurality of instances of the periodic sequence;
• and
• select an instance of the periodic sequence with the highest correlation to the confined values as an observed periodic sequence.

A system to detect a periodic sequence, the system comprising:

• a storage medium comprising a periodic sequence;
• a read channel configured to read the periodic sequence;
• a sequence detector comprising
• a value detector module configured to detect a plurality of values from the periodic sequence;
• a transformation module configured to transform the plurality of values into transformed values;
• a confinement module configured to confine the transformed values to a limited set of confined values;
• a correlation module configured to correlate the confined values with a plurality of instances of the periodic sequence;
• and
• a selection module configured to select an instance of the periodic sequence with the highest correlation to the confined values as an observed periodic sequence.

A method for deploying computer infrastructure, comprising integrating computer-readable code into a computing system, wherein the code in combination with the computing system is capable of performing the following:

• detect a plurality of values of a periodic sequence that comprises the instance ‘5 5 4 4’;
• transform each value uk of the plurality of values into the transformed value rk using the equation rk=2uk−9;
• confine each transformed value rk to a first confined value in response to the value being greater than or substantially equivalent to the first confined value and to a second confined value in response to the value being less than or substantially equivalent to the second confined value;
• correlate the confined values with a plurality of instances of the periodic sequence;
• and
• select the instance of the periodic sequence with the highest correlation to the confined values as an observed periodic sequence.