Method for controlling the lateral position of a tape head of a magnetic tape drive

A computer program product for controlling a lateral position of a tape head of a magnetic tape drive, the computer program product comprising:

• a non-transitory storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method comprising:
• determining a first servo signal by reading position marks from a first servo band on a magnetic tape using a first sensor,
• determining a second servo signal by reading position marks from a second servo band on the magnetic tape using a second sensor,
• delaying the first servo signal relative to the second servo signal by a delay to create a delayed second servo signal, wherein the delay is based on the frequency (f) of a longitudinal oscillation of the magnetic tape,
• calculating an average signal based on the first servo signal and the delayed second servo signal,
• determining a servo information from the average signal, the servo information being indicative of a deviation of the lateral position of the tape head from an ideal lateral position of the tape head relative to the magnetic tape, and
• controlling the tape head to adjust its lateral position such that the deviation is decreased.

A magnetic tape drive for reading data from a magnetic tape using a tape head, the tape head comprising at least two sensors adapted to determine a signal from a magnetic tape, the magnetic tape comprising at least two servo bands, the servo bands comprising position marks indicative of a lateral position of the tape head relative to the magnetic tape, the position marks providing identical lateral position information for each servo band of the magnetic tape, the tape head being in physical contact with the magnetic tape, the physical contact causing a longitudinal oscillation of the magnetic tape in case the magnetic tape is passing the tape head with a velocity which is non-zero, the oscillation having a frequency f, the magnetic tape drive being adapted to:

• determine a first servo signal by reading the position marks from a first servo band using a first sensor,
• determine a second servo signal by reading the position marks from a second servo band using a second sensor,
• delay the first servo signal relative to the second servo signal by a delay, the delaying resulting in a delayed second servo signal, the delay depending on the frequency f of the longitudinal oscillation of the magnetic tape,
• determine the average signal of the first servo signal and the delayed second servo signal,
• determine a servo information from the average signal, the servo information being indicative of a deviation of the lateral position of the tape head from an ideal lateral position of the tape head relative to the magnetic tape, and
• re-adjust the lateral position of the tape head such that the determined deviation is decreased.