Nonlinearity measuring method, nonlinearity measuring unit, magnetic recording/regenerating unit and LSI for magnetic recording/regenerating

A nonlinearity measuring unit for calculating non linear transition shift (NLTS) in magnetic recording/regenerating in a medium, comprising:

• a first measuring section measuring a first predetermined higher harmonic component from a regenerated signal of a reference signal magnetically recorded on the medium;
• a second measuring section measuring a second predetermined higher harmonic component from its regenerated signal with respect to each of the plural kinds of signals to be measured magnetically recorded on the medium;
• and
• a calculating section calculating the NLTS from said first predetermined higher harmonic component and said second predetermined higher harmonic component corresponding to each of the signals to be measured,
• wherein each of said plural kinds of signals to be measured includes a magnetization inversion pattern string P1 preceding objective bits to be measured of said NLTS.

A magnetic recording/regenerating unit, comprising:

• a first measuring section for measuring a first predetermined higher harmonic component from a regenerated signal of a reference signal magnetically recorded on a medium;
• a second measuring section for measuring a second predetermined higher harmonic component from its regenerated signal with respect to each of the plural kinds of signals to be measured magnetically recorded on the medium;
• and
• a calculating section for calculating non linear transition shift (NLTS) in magnetic recording/regenerating in the medium from said first predetermined higher harmonic component and said second predetermined higher harmonic component corresponding to each of the signals to be measured,
• wherein each of said plural kinds of signals to be measured includes a magnetization inversion pattern string P1 preceding objective bits to be measured of said NLTS.

An LSI for magnetic recording/regenerating, comprising:

• a first measuring section measuring a first predetermined higher harmonic component from a regenerated signal of a reference signal magnetically recorded on a medium;
• a second measuring section measuring a second predetermined higher harmonic component from its regenerated signal with respect to each of the plural kinds of signals to be measured magnetically recorded on the medium;
• and
• a calculating section calculating non linear transition shift (NLTS) in magnetic recording/regenerating in the medium from said first predetermined higher harmonic component and said second predetermined higher harmonic component corresponding to each of the signals to be measured,
• wherein each of said plural kinds of signals to be measured includes a magnetization inversion pattern string P1 preceding objective bits to be measured of said NLTS.